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== About this page==
 
== About this page==
  
−
Below you can find a list of intentional changes since the [[User_Changes_2.6.2|previous release]] that can change the behaviour of previously working code, along with why these changes were performed and how you can adapt your code if you are affected by them. The list of new features can be found [[FPC_New_Features_Trunk|here]].
+
Listed below are intentional changes made to the FPC compiler (trunk) since the [[User_Changes_3.2.2|previous release]] that may break existing code. The list includes reasons why these changes have been implemented, and suggestions for how you might adapt your code if you find that previously working code has been adversely affected by these recent changes.  
 +
 
 +
The list of new features that do not break existing code can be found [[FPC_New_Features_Trunk|here]].
 +
 
 +
Please add revision numbers to the entries from now on. This facilitates moving merged items to the user changes of a release.
  
 
== All systems ==
 
== All systems ==
  
−
=== Implementation changes ===
+
=== Language Changes ===
  
−
==== Exception type for object reference checking changed ====
+
==== Precedence of the IS operator changed ====
−
* '''Old behaviour''': When object reference checking (''-CR'' or ''{$OBJECTCHECKS ON}'') is enabled and the unit ''SysUtils'' is used then an exception of class ''Exception'' with localizeable message ''Unknown runtime error 210'' is created.
+
* '''Old behaviour''': The IS operator had the same precedence as the multiplication, division etc. operators.
−
* '''New behaviour''': Now an exception of class ''EObjectCheck'' with localizeable message ''Object reference is Nil'' is created.
+
* '''New behaviour''': The IS operator has the same precedence as the comparison operators.
−
* '''Reason''': All other runtime errors in the 2xx range have approbiate exception types, so it is only natural to have an explicit type for runtime error 210 as well.
+
* '''Reason''': Bug, see [https://bugs.freepascal.org/view.php?id=35909].
−
* '''Remedy''': If you checked an exception for the message ''Unknown runtime error 210'' you should now check for the exception class ''EObjectCheck''.
+
* '''Remedy''': Add parenthesis where needed.
  
−
==== Literal storage memory has been made read-only ====
+
==== Visibilities of members of generic specializations ====
 +
* '''Old behaviour''': When a generic is specialized then visibility checks are handled as if the generic was declared in the current unit.
 +
* '''New behaviour''': When a generic is specialized then visibility checks are handled according to where the generic is declared.
 +
* '''Reason''': Delphi-compatibility, but also a bug in how visibilities are supposed to work.
 +
* '''Remedy''': Rework your code to adhere to the new restrictions.
  
−
* '''Old behaviour''': read-only data segments were de-facto not supported, all data could be modified at runtime even if it was not intended for modification (except in some cases on Darwin). This could cause nasty side-effects, e.g the following code:
+
=== Implementation Changes ===
  
−
<syntaxhighlight>
+
==== Disabled default support for automatic conversions of regular arrays to dynamic arrays ====
−
uses sysutils;
+
* '''Old behaviour''': In FPC and ObjFPC modes, by default the compiler could automatically convert a regular array to a dynamic array.
−
var
+
* '''New behaviour''': By default, the compiler no longer automatically converts regular arrays to dynamic arrays in any syntax mode.
−
  s: ansistring;
+
* '''Reason''': When passing a dynamic array by value, modifications to its contents by the callee are also visible on the caller side. However, if an array is implicitly converted to a dynamic array, the result is a temporary value and hence changes are lost. This issue came up when adding [https://bugs.freepascal.org/view.php?id=35580 TStream.Read() overloads].
−
begin
+
* '''Remedy''': Either change the code so it no longer assigns regular arrays to dynamic arrays, or add ''{$modeswitch arraytodynarray}''  
−
  s := 'ansi string';
+
* '''Example''': this program demonstrates the issue that appeared with the TStream.Read() overloads that were added (originally, only the the version with the untyped variable existed)
−
  Writeln(AnsiStrUpper(pchar(s)));
+
 
−
  s := 'ansi string';
+
<syntaxhighlight lang="pascal">
−
  Writeln(s);
+
{$mode objfpc}
−
end.
+
type
−
</syntaxhighlight>
+
  tdynarray = array of byte;
  
−
would modify the content of data segment and print
+
procedure test(var arr); overload;
 +
begin
 +
  pbyte(arr)[0]:=1;
 +
end;
  
−
ANSI STRING
+
procedure test(arr: tdynarray); overload;
−
ANSI STRING
+
begin
 +
  test[0]:=1;
 +
end;
  
−
* '''New behaviour''': Data that is not intended to be modified at runtime is put into read-only segment. This includes literal constants used in expressions and typed constants declared in {$J-} state. The code which modifies such data, like the example above, will now crash.
+
var
−
* '''Reason''': This is consistent with the way other compilers, including Delphi, work. Keeping as much as possible data read-only improves loading speed of programs because read-only pages can be mapped directly on executable file, and also improves security of programs.
+
  regulararray: array[1..1] of byte;
−
* '''Remedy''': Depends on the code. In the example above, it is sufficient to call <tt>UniqueString(s)</tt> before <tt>AnsiStrUpper</tt>
+
begin
 +
  regulararray[1]:=0;
 +
  test(arr);
 +
  writeln(arr[0]); // writes 0, because it calls test(tdynarr)
 +
end.
 +
</syntaxhighlight>
 +
* '''svn''': 42118
  
−
=== Unit changes ===
+
==== Directive clause ''[…]'' no longer useable with modeswitch ''PrefixedAttributes'' ====
 +
* '''Old behaviour''': A function/procedure/method or procedure/method variable type could be followed by a directive clause in square brackets (''[…]'') that contains the directives for the routine or type (e.g. calling convention).
 +
* '''New behaviour''': If the modeswitch ''PrefixedAttributes'' is enabled (which is the default in modes ''Delphi'' and ''DelphiUnicode'') the directive clause in square brackets is no longer allowed.
 +
* '''Reason''': As custom attributes are bound to a type/property in a way that looks ambiguous to a directive clause and this ambiguity is not easily solved in the parser it is better to disable this feature.
 +
* '''Remedy''':
 +
** don't set (in non-''Delphi'' modes) or disable modeswitch ''PrefixedAttributes'' (in ''Delphi'' modes) if you don't use attributes (''{$modeswitch PrefixedAttributes-}'')
 +
** rework your directive clause:
 +
<syntaxhighlight lang="pascal">
 +
// this
 +
procedure Test; cdecl; [public,alias:'foo']
 +
begin
 +
end;
  
−
==== TBookmark TBookmarkstr and TDataset.Bookmark change to Delphi2009+ compatible definitions  ====
+
// becomes this
−
* '''Old behaviour''': TDataset.Bookmark was of type TBookmarkstr, TBookmarkstr=string, Tbookmark=pointer
+
procedure Test; cdecl; public; alias:'foo';
−
* '''New behaviour''': TDataset.Bookmark is of type TBookmark, TBookmarkstr=ansistring, TBookmark=TBytes.  TBookmarkstr will trigger a deprecated warning.
+
begin
−
* '''Reason''': D2009+ compatibility, where probably the fact that string became a 2-byte encoding was the trigger.
+
end;
−
* '''Remedy''': Adjust typing in descendents and using code accordingly.
+
</syntaxhighlight>
 +
* '''svn''': 42402
  
−
==== FileNameCaseSensitive and FileNameCasePreserving in unit System ====
+
==== Type information contains reference to attribute table ====
−
* '''Old behaviour''': There was only one constant (FileNameCaseSensitive) which signalized behaviour of the respective target platform with regard to the case in filenames. This was often set to true also on platforms not really treating filenames in case sensitive manner (e.g. Win32 and Win64).
+
* '''Old behavior''': The first field of the data represented by ''TTypeData'' is whatever the sub branch of the case statement for the type contains.
−
* '''New behaviour''': FileNameCaseSensitive is set to true only on platforms which really treat filenames in case sensitive manner and FileNameCasePreserving constant is added to unit system of all platforms to signalize whether the case in filenames supplied when creating or renaming them is preserved or not. This might possibly break existing user code relying on the previous (sometimes incorrect) value of FileNameCaseSensitive.
+
* '''New behavior''': The first field of the data represented by ''TTypeData'' is a reference to the custom attributes that are attributed to the type, only then the type specific fields follow.
−
* '''Reason''': In reality, there are two distinct types of behaviour. If a platform is case sensitive, searching for file "a" will never result in finding file "A" whereas case insensitive platform will happily return "A" if such a file is found on the disk. If a platform is case preserving, it will store file "a" as "a" on disk whereas case non-preserving platform may convert the filenames to uppercase before storing them on disk (i.e. file "a" is in reality stored as "A"). Case non-preserving platforms are never case sensitive, but case preserving platforms may or may not be case sensitive at the same time.
+
* '''Reason''': Any type can have attributes, so it make sense to provide this is a common location instead of having to parse the different types.
−
* '''Remedy''': Review your existing code using FileNameCaseSensitive, check which of the two properties described above fit the particular purpose in your case and change to FileNameCasePreserving where appropriate.
+
* '''Remedy''':
 +
** If you use the records provided by the ''TypInfo'' unit no changes ''should'' be necessary (same for the ''Rtti'' unit).
 +
** If you directly access the binary data you need handle an additional ''Pointer'' field at the beginning of the ''TTypeData'' area and possibly correct the alignment for platforms that have strict alignment requirements (e.g. ARM or M68k).
 +
* '''svn''': 42375
 +
==== Explicit values for enumeration types are limited to low(longint) ... high(longint) ====
 +
* '''Old behavior''': The compiler accepted every integer value as explicit enumeration value. The value was silently reduced to the longint range if it fell outside of that range
 +
* '''New behavior''': The compiler throws an error (FPC mode) or a warning (Delphi mode) if an explicit enumeration value lies outside the longint range.
 +
* '''Reason''': ''Type TEnum = (a = $ffffffff);'' resulted in an enum with size 1 instead of 4 as would be expected, because  $ffffffff was interpreted as "-1".
 +
* '''Remedy''': Add Longint typecasts to values outside the valid range of a Longint.
  
−
==== Some longtime deprecated functions in unit Unix have been removed. ====
+
==== Comp as a type rename of Int64 instead of an alias ====
−
* '''Old behaviour''': Unix.(f)statfs, Unix.shell and Unix.fsync symbols existed in unit Unix
+
* '''Old behavior''': On non-x86 as well as Win64 the Comp type is declared as an alias to Int64 (''Comp = Int64'').
−
* '''New behaviour''': Unix.(f)statfs, Unix.shell and Unix.fsync were removed
+
* '''New behavior''': On non-x86 as well as Win64 the Comp type is declared as a type rename of Int64 (''Comp = type Int64'').
−
* '''Reason''': These were helper functions and leftovers from the 1.0.x->2.0.0 conversion, deprecated since 2007. Shell had non standarized conventions
+
* '''Reason''':
−
* '''Remedy''': All but shell: use the same functions with a "fp" prefix.  Shell: use fpsystem. If you checked the return value for other values than -1, a modification of the errorchecking might be necessary. Refer to your *nix documention, or have a look at the transformfpsystemtoshell function in tests/util/redir.pp in the FPC sources to see what a quick fix looks like.
+
** This allows overloads of ''Comp'' and ''Int64'' methods/functions
 +
** This allows to better detect properties of type ''Comp''
 +
** Compatibility with Delphi for Win64 which applied the same reasoning
 +
* '''Remedy''': If you relied on ''Comp'' being able to be passed to ''Int64'' variables/parameters either include typecasts or add overloads for ''Comp''.
 +
* '''svn''': 43775
  
−
==== statfs has been renamed to fpstatfs ====
+
==== Routines that only differ in result type ====
−
* '''Old behaviour''': One overload of fpstatfs was not renamed from statfs to fpstatfs (around 2.4.0)
+
* '''Old behaviour:''' It was possible to declare routines (functions/procedures/methods) that only differ in their result type.
−
* '''New behaviour''': The function has been renamed.
+
* '''New behaviour:''' It is no longer possible to declare routines that only differ in their result type.
−
* '''Reason''': Should have been done in 2.4.0 to begin with, but was postponed several times to coincide with a major version change.  
+
* '''Reason:''' It makes no sense to allow this as there are situations where the compiler will not be able to determine which function to call (e.g. a simple call to a function ''Foo'' without using the result).
−
* '''Remedy''': Use fpstatfs
+
* '''Remedy:''' Correctly declare overloads.
 +
* '''Notes:'''
 +
** As the JVM allows covariant interface implementations such overloads are still allowed inside classes for the JVM target.
 +
** Operator overloads (especially assignment operators) that only differ in result type are still allowed.
 +
* '''svn:''' 45973
  
−
==== RTLeventsync has been removed ====
+
==== Open Strings mode enabled by default in mode Delphi ====
−
* '''Old behaviour''': The thread manager record contained an ''rtleventsync'' field, and the RTL had an ''RTLeventsync'' routine. No functionality for this routine was implemented in the FPC-supplied thread manager for any platform.
+
* '''Old behaviour:''' The Open Strings feature (directive ''$OpenStrings'' or ''$P'') was not enabled in mode Delphi.
−
* '''New behaviour''': The field and routine have been removed.
+
* '''New behaviour:''' The Open Strings feature (directive ''$OpenStrings'' or ''$P'') is enabled in mode Delphi.
−
* '''Reason''': The functionality was not available on any platform by default, and we're not aware of any third party thread manager that implemented them or third party code that relied on it. Additionally, the routine was documented as "Obsolete. Don't use.", without any explanation of what it was supposed to do.
+
* '''Reason:''' Delphi compatibility.
−
* '''Remedy''': Remove any such calls from your code.
+
* '''Remedy:''' If you have assembly routines with a ''var'' parameter of type ''ShortString'' then you also need to handle the hidden ''High'' parameter that is added for the Open String or you need to disable Open Strings for that routine.
 +
* '''git:''' [https://gitlab.com/freepascal.org/fpc/source/-/commit/188cac3bc6dc666167aacf47fedff1a81d378137 188cac3b]
  
−
==== TODBCConnection (odbcconn) No longer autocommit  ====
+
=== Unit changes ===
−
* '''Old behaviour''': Autocommit was enabled: Every change was committed to the database at once.
 
−
* '''New behaviour''': Changes must be committed explicitly using Transaction.Commit
 
−
* '''Reason''': Transactions are useless if everything is autocommitted: in particular; rollback is not possible.
 
−
* '''Remedy''': You can enable autocommit by specifying AUTOCOMMIT=1 in the params of TODBCConnection.
 
  
−
==== FPCanvas Strikethough property spelling fixed to StrikeThrough ====
+
==== System - TVariantManager ====
−
* '''Old behaviour''': Fonts had a Striketrough property which is a typo.
 
−
* '''New behaviour''': The property has been changed to Strikethrough.
 
−
* '''Reason''': Spelling fix.
 
−
* '''Remedy''': Please rename property calls in your code. FPC 2.6.2 contains both versions so there is a window for adaptation.
 
  
−
==== TVersionInfo (fileinfo unit) re-implemented in a platform independent way ====
+
* '''Old behaviour:''' ''TVariantManager.olevarfromint'' has a ''source'' parameter of type ''LongInt''.
−
* '''Old behaviour''': GetVersionSetting method would read file information.
+
* '''New behaviour:''' ''TVariantManager.olevarfromint'' has a ''source'' parameter of type ''Int64''.
−
* '''New behaviour''': The ReadFileInfo call will read the information. The global GetProgramVersion call will extract the program major/minor/revision/build version in 1 single call.
+
* '''Reason for change:''' 64-bit values couldn't be correctly converted to an OleVariant.
−
* '''Reason''': The unit now uses FPC resources on all platforms, and can now be used to read external resources.
+
* '''Remedy:''' If you implemented your own variant manager then adjust the method signature and handle the range parameter accordingly.
−
* '''Remedy''': Use the ReadFileInfo call to get the version information. Add relevant units for desired resource support to your uses clause; e.g. if you need to read Windows .exe file info, add winpeimagereader
+
* '''svn:''' 41570
  
−
==== TDBF unit deprecation removed ====
+
==== System - buffering of output to text files ====
−
* '''Old behaviour''': the TDBF units were marked deprecated because the original maintainer of the upstream project stopped maintenance. However, the unit remained in fcl-db and patches were still accepted.
 
−
* '''New behaviour''': the deprecation warning is removed. There is a new upstream project maintainer and FPC database devs support this unit again. Note: there is a known problem: TDBF will not work on ARM processors due to alignment issues (http://bugs.freepascal.org/view.php?id=22177). This will only be fixed if a patch is provided, and proven to not produce regressions (e.g. by tests in the FPC db test framework)
 
−
* '''Remedy''': N/A
 
  
−
=== Language Changes ===
+
* '''Old behaviour:''' Buffering was disabled only for output to text files associated with character devices (Linux, BSD targets, OS/2), or for output to Input, Output and StdErr regardless of their possible redirection (Win32/Win64, AIX, Haiku, BeOS, Solaris).
 +
* '''New behaviour:''' Buffering is disabled for output to text files associated with character devices, pipes and sockets (the latter only if the particular target supports accessing sockets as files - Unix targets).
 +
* '''Reason for change:''' The same behaviour should be ensured on all supported targets whenever possible. Output to pipes and sockets should be performed immediately, equally to output to character devices (typically console) - in case of console users may be waiting for the output, in case of pipes and sockets some other program is waiting for this output and buffering is not appropriate. Seeking is not attempted in SeekEof implementation for files associated with character devices, pipes and sockets, because these files are usually not seekable anyway (instead, reading is performed until the end of the input stream is reached).
 +
* '''Remedy:''' Buffering of a particular file may be controlled programmatically / changed from the default behaviour if necessary. In particular, perform TextRec(YourTextFile).FlushFunc:=nil immediately after opening the text file (i.e. after calling Rewrite or after starting the program in case of Input, Output and StdErr) and before performing any output to this text to enable buffering using the default buffer, or TextRec(YourTextFile).FlushFunc:=TextRec(YourTextFile).FileWriteFunc to disable buffering.
 +
* '''svn:''' 46863
  
−
==== Variant overload preference for string types ====
+
==== System - type returned by BasicEventCreate on Windows ====
−
* '''Old behaviour''': Preference for string types was (from better to worse): ShortString, AnsiString, WideString, UnicodeString
 
−
* '''New behaviour''': Preference for string types now (from better to worse): WideString, UnicodeString, AnsiString, ShortString
 
−
* '''Reason''': Unicode characters and codepage information will not lose during the conversion and unicode Delphi compatibility.
 
−
* '''Remedy''': Use explicit conversion (e.g. ShortString(V)) if it is needed to pass variant to routine with paticular string type argument.
 
  
−
==== Default values in implementation but not in interface/forward declaration ====
+
* '''Old behaviour:''' BasicEventCreate returns a pointer to a record which contains the Windows Event handle as well as the last error code after a failed wait. This record was however only provided in the implementation section of the ''System'' unit.
−
* '''Old behaviour''': The implementation of a routine could declare default values even if the interface declaration did not have any.
+
* '''New behaviour:''' BasicEventCreate returns solely the Windows Event handle.
−
* '''New behaviour''': Default values, if any, must be specified in the interface. They can be repeated in the implementation, but that is not required (just like it was not in the past).
+
* '''Reason for change:''' This way the returned handle can be directly used in the Windows ''Wait*''-functions which is especially apparent in ''TEventObject.Handle''.
−
* '''Reason''': Default parameters specified only in the implementation are not, and cannot, be propagated to the interface since a unit's interface can be used before the implementation has been parsed (see http://bugs.freepascal.org/view.php?id=19434), Delphi compatibility.
+
* '''Remedy:''' If you need the last error code after a failed wait, use ''GetLastOSError'' instead.
−
* '''Remedy''': Always specify default parameter values (also) in the interface/forward declaration of a routine.
+
* '''svn:''' 49068
  
−
==== Default values are now properly typechecked ====
+
==== System - Ref. count of strings ====
−
* '''Old behaviour''': The compiler did not detect default values for parameters of which the type did not in any way correspond to the parameter type.
 
−
* '''New behaviour''': The compiler now properly checks whether the type of the constant matches the parameter's type when parsing default values.
 
−
* '''Reason''': Proper type checking is one of the fundamental properties of the Pascal language; Delphi compatibility.
 
−
* '''Remedy''': Add a typecast around default values that now result in compiler errors, or correct the type of such parameters.
 
  
−
==== Recursive parameterless function calls in MacPas mode ====
+
* '''Old behaviour:''' Reference counter of strings was a ''SizeInt''
−
* '''Old behaviour''': When using the name of a function inside its own body on the right hand side of an expression, the compiler treated this as a read of the last value assigned to the function result in MacPas mode.
+
* '''New behaviour:''' Reference counter of strings is now a ''Longint'' on 64 Bit platforms and ''SizeInt'' on all other platforms.
−
* '''New behaviour''': The compiler will now treat such occurrences of the function name as recursive function calls in MacPas mode.
+
* '''Reason for change:''' Better alignment of strings
−
* '''Reason''': Compatibility with Mac Pascal compilers.
+
* '''Remedy:''' Call ''System.StringRefCount'' instead of trying to access the ref. count field by pointer operations or other tricks.
−
* '''Remedy''': If you wish to read the current function result value, compile the code with ''{$modeswitch result}'', after which you can use the ''result'' alias for that value. Note that the use of this mode switch can also result in [[User_Changes_2.6.0#Implicit_.22result.22_variable_in_MacPas_mode|different behaviour]] compared to traditional Mac Pascal compilers.
+
* '''git:''' [https://gitlab.com/freepascal.org/fpc/source/-/commit/ee10850a5793b69b19dc82b9c28342bdd0018f2e ee10850a57]
  
−
==== "''strict protected''" visibility modifier ====
+
==== System.UITypes - function TRectF.Union changed to procedure ====
−
* '''Old behaviour''': ''strict protected'' did not correctly limit the visibility of symbols declared in different units.
 
−
* '''New behaviour''': ''strict protected'' symbols can now only be accessed from descendent classes, regardless of where they are defined.
 
−
* '''Reason''': Fix behaviour to conform to specification/documentation, Delphi compatibility.
 
−
* '''Remedy''': Use ''protected'' or ''public'' if less strict accessibility checks are desired.
 
  
−
==== support for type helpers added ====
+
* '''Old behaviour:''' ''function TRectF.Union(const r: TRectF): TRectF;''
−
* '''Old behaviour''': In modes ''ObjFPC'' and ''MacPas'' it was possible to declare a unique type of a type ''helper''.
+
* '''New behaviour:''' ''procedure TRectF.Union(const r: TRectF);''
−
* '''New behaviour''': The compiler now interprets the keyword ''helper'' as a helper type if it immediately follows the ''type'' keyword (but only if the mode is ''ObjFPC'' or ''MacPas'' or the mode switch ''Class'' is set).
+
* '''Reason for change:''' Delphi compatibility and also compatibility with TRect.Union
−
* '''Example''':
+
* '''Remedy:''' Call ''class function TRectF.Union'' instead.
−
<syntaxhighlight>
+
* '''git:''' [https://gitlab.com/freepascal.org/fpc/source/-/commit/5109f0ba444c85d2577023ce5fbdc2ddffc267c8 5109f0ba]
−
{$mode objfpc}
 
−
type
 
−
  helper = LongInt;
 
  
−
  otherhelper = type helper;
+
==== 64-bit values in OleVariant ====
−
</syntaxhighlight>
 
−
The above code will no longer compile.
 
−
* '''Reason''': ''type helper'' is a more logical way to declare helpers for primitive types than Delphi's ''record helper'' is.
 
−
* '''Remedy''': Escape the keyword ''helper'' using a ''&''. E.g.:
 
−
<syntaxhighlight>
 
−
{$mode objfpc}
 
−
type
 
−
  helper = LongInt;
 
  
−
  otherhelper = type &helper;
+
* '''Old behaviour:''' If a 64-bit value (''Int64'', ''QWord'') is assigned to an OleVariant its type is ''varInteger'' and only the lower 32-bit are available.
−
</syntaxhighlight>
+
* '''New behaviour:''' If a 64-bit value (''Int64'', ''QWord'') is assigned to an OleVariant its type is either ''varInt64'' or ''varQWord'' depending on the input type.
 +
* '''Reason for change:''' 64-bit values weren't correctly represented. This change is also Delphi compatible.
 +
* '''Remedy:''' Ensure that you handle 64-bit values correctly when using OleVariant.
 +
* '''svn:''' 41571
  
−
==== "''strict protected''" and "''protected''" visibility modifier in extended records ====
+
==== Classes TCollection.Move ====
−
* '''Old behaviour''': ''strict protected'' and ''protected'' could be used used in extended records.
+
* '''Old behaviour:''' If a TCollection.Descendant called Move() this would invoke System.Move.
−
* '''New behaviour''': ''strict protected'' and ''protected'' are no longer allowed in extended records.
+
* '''New behaviour:''' If a TCollection.Descendant called Move() this invokes TCollection.Move.
−
* '''Reason''': The only difference between ''(strict) protected'' and ''(strict) private'' is that the former allows you to access members of a parent class or object. As records don't support inheritence it makes no sense to support ''(strict) protected'' in them. This is also Delphi-compatible.
+
* '''Reason for change:''' New feature in TCollection: move, for consistency with other classes.
−
* '''Remedy''': Use ''private'' instead of ''protected'' and ''strict private'' instead of ''strict protected''.
+
* '''Remedy:''' prepend the Move() call with the system unit name: System.move().
 +
* '''svn:''' 41795
  
−
==== "''static''" directive on non-class methods ====
+
==== Math Min/MaxSingle/Double ====
−
* '''Old behaviour''': It was possible to use the ''static'' on normal, non-''class'' methods
+
* '''Old behaviour:''' MinSingle/MaxSingle/MinDouble/MaxDouble were set to a small/big value close to the smallest/biggest possible value.
−
* '''New behaviour''': The compiler now generates an error if ''static'' is used on normal, non-''class'' methods (except in ''object'' types)
+
* '''New behaviour:''' The constants represent now the smallest/biggest positive normal numbers.
−
* '''Reason''': It is only correct to leave out the ''Self'' parameter if it is a class method. This is also Delphi compatible.
+
* '''Reason for change:''' Consistency (this is also Delphi compatibility), see https://gitlab.com/freepascal.org/fpc/source/-/issues/36870.
−
* '''Remedy''': Prepend the ''class'' keyword to the method.
+
* '''Remedy:''' If the code really depends on the old values, rename them and use them as renamed.
 +
* '''svn:''' 44714
  
−
==== "''static''" directive on class operators ====
+
==== Random generator ====
−
* '''Old behaviour''': It was possible to use the ''static'' on class operators.
+
* '''Old behaviour:''' FPC uses a Mersenne twister generate random numbers
−
* '''New behaviour''': The compiler now generates an error if ''static'' is used on class operators.
+
* '''New behaviour:''' Now it uses Xoshiro128**
−
* '''Reason''': Class operators are by definition static, thus the ''static'' would be redundant. This is also Delphi compatible.
+
* '''Reason for change:''' Xoshiro128** is faster, has a much smaller memory footprint and generates better random numbers.
−
* '''Remedy''': Remove the ''static'' keyword from class operators.
+
* '''Remedy:''' When using a certain randseed, another random sequence is generated, but as the PRNG is considered as an implementation detail, this does not hurt.
 +
* '''git:''' 91cf1774
  
−
====Classes implementing forward-declared interfaces====
+
==== Types.TPointF.operator * ====
 +
* '''Old behaviour:''' for <code>a, b: TPointF</code>, <code>a * b</code> is a synonym for <code>a.DotProduct(b)</code>: it returns a <code>single</code>, scalar product of two input vectors.
 +
* '''New behaviour:''' <code>a * b</code> does a component-wise multiplication and returns <code>TPointF</code>.
 +
* '''Reason for change''': Virtually all technologies that have a notion of vectors use <code>*</code> for component-wise multiplication. Delphi with its <code>System.Types</code> is among these technologies.
 +
* '''Remedy:''' Use newly-introduced <code>a ** b</code>, or <code>a.DotProduct(b)</code> if you need Delphi compatibility.
 +
* '''git:''' [https://gitlab.com/freepascal.org/fpc/source/-/commit/f1e391fb415239d926c4f23babe812e67824ef95 f1e391fb]
  
−
* '''Old behaviour''': It was possible to declare classes as implementing a forward-declared interface.
+
==== CocoaAll ====
−
* '''New behaviour''': Classes can no longer implement forward-declared interfaces.
+
===== CoreImage Framework Linking =====
−
* '''Reason''': This occasionally [http://bugs.freepascal.org/view.php?id=24184 caused crashes], the compiler did not check in such a case whether the class actually implemented the methods of that interface. Recent versions of Delphi also reject such constructs.
+
* '''Old behaviour''': Starting with FPC 3.2.0, the ''CocoaAll'' unit linked caused the ''CoreImage'' framework to be linked.
−
* '''Remedy''': If there is a cyclic dependency between a class and an interface, use a forward declaration for the class instead.
+
* '''New behaviour''': The ''CocoaAll'' unit no longer causes the ''CoreImage'' framework to be linked.
 +
* '''Reason for change''': The ''CoreImage'' framework is not available on OS X 10.10 and earlier (it's part of ''QuartzCore'' there, and does not exist at all on some even older versions).
 +
* '''Remedy''': If you use functionality that is only available as part of the separate ''CoreImage'' framework, explicitly link it in your program using the ''{$linkframework CoreImage}'' directive.
 +
* '''svn''': 45767
  
−
== Unix platforms ==
+
==== DB ====
 +
===== TMSSQLConnection uses TDS protocol version 7.3 (MS SQL Server 2008) =====
 +
* '''Old behaviour:''' TMSSQLConnection used TDS protocol version 7.0 (MS SQL Server 2000).
 +
* '''New behaviour:''' TMSSQLConnection uses TDS protocol version 7.3 (MS SQL Server 2008).
 +
* '''Reason for change:''' native support for new data types introduced in MS SQL Server 2008 (like DATE, TIME, DATETIME2). FreeTDS client library version 0.95 or higher required.
 +
* '''svn''': 42737
  
−
=== cthreads: critical sections and recursive mutex support ===
+
===== DB.TFieldType: new types added =====
−
* '''Old behaviour''': If the ''cthreads'' unit thread manager was used on a platform without recursive mutex support, critical sections were non-reentrant.
+
* '''Old behaviour:''' .
−
* '''New behaviour''': Initialising a critical section under the above circumstances will now result in a run time error.
+
* '''New behaviour:''' Some of new Delphi field types were added (ftOraTimeStamp, ftOraInterval, ftLongWord, ftShortint, ftByte, ftExtended) + corresponding classes TLongWordField, TShortIntField, TByteField; Later were added also ftSingle and TExtendedField, TSingleField
−
* '''Reason''': One of the basic properties of (Delphi/Windows-compatible) critical sections is that they are reentrant, and that is how they are generally used in Pascal code.
+
* '''Reason for change:''' align with Delphi and open space for support of short integer and unsigned integer data types
−
* '''Remedy''': Use an RTLEvent instead if reentrancy is not required.
+
* '''svn''': 47217, 47219, 47220, 47221; '''git''': c46b45bf
  
 +
==== DaemonApp ====
 +
===== TDaemonThread =====
 +
* '''Old behaviour:''' The virtual method ''TDaemonThread.HandleControlCode'' takes a single ''DWord'' parameter containing the control code.
 +
* '''New behaviour:''' The virtual method ''TDaemonThread.HandleControlCode'' takes three parameters of which the first is the control code, the other two are an additional event type and event data.
 +
* '''Reason for change:''' Allow for additional event data to be passed along which is required for comfortable handling of additional control codes provided on Windows.
 +
* '''svn''': 46327
  
−
== Darwin/i386 and iPhoneSim/i386 ==
+
===== TDaemon =====
 +
* '''Old behaviour:''' If an event handler is assigned to ''OnControlCode'' then it will be called if the daemon receives a control code.
 +
* '''New behaviour:''' If an event handler is assigned to ''OnControlCodeEvent'' and that sets the ''AHandled'' parameter to ''True'' then ''OnControlCode'' won't be called, otherwise it will be called if assigned.
 +
* '''Reason for change:''' This was necessary to implement the handling of additional arguments for control codes with as few backwards incompatible changes as possible.
 +
* '''svn''': 46327
  
−
=== Location of certain function result types ===
+
==== FileInfo ====
−
* '''Old behaviour''': Small records and method pointers were always returned according to the official ABI.
+
* '''Old behaviour:''' The ''FileInfo'' unit is part of the ''fcl-base'' package.
−
* '''New behaviour''': When a calling convention other than ''cdecl'', ''cppdecl'' or ''mwpascal'' is used, the same convention as on other platforms is now used.
+
* '''New behaviour:''' The ''FileInfo'' unit is part of the ''fcl-extra'' package.
−
* '''Reason''': Better compatibility with assembler code written for other platforms.
+
* '''Reason for change:''' Breaks up a cycle in build dependencies after introducing a RC file parser into ''fcl-res''. This should only affect users that compile trunk due to stale PPU files in the old location or that use a software distribution that splits the FPC packages (like Debian).
−
* '''Remedy''': Update your assembler code, or better: if possible, convert it to Pascal.
+
* '''svn''': 46392
  
−
== All Darwin/Mac OS X/iOS ==
+
==== Sha1 ====
−
===MacOSAll unit: changed parameter and opaque types===
+
* '''Old behaviour:''' Sha1file silently did nothing on file not found.
 +
* '''New behaviour:''' sha1file now raises sysconst.sfilenotfound exception on fle not found.
 +
* '''Reason for change:''' Behaviour was not logical, other units in the same package already used sysutils.
 +
* '''svn''': 49166
  
−
* '''Change''': The headers have been updated to the Mac OS X 10.8 SDK, and in this process a number of signatures have been changed/corrected, and several opaque types have been changed from ^SInt32 into pointers to different/incompatible empty records.
+
==== Image ====
−
* '''Reason''': The reasons for the signature changes are detailed below. The opaque types have been made incompatible so that the compiler can give error messages when trying to use one opaque type instead of another (e.g., in the past the compiler did not complain when passing a ControlRef to a routine that expected a WindowPtr).
+
===== FreeType: include bearings and invisible characters into text bounds =====
−
* '''Remedy''': Adjust your code to conform to the new signatures. Regarding the opaque types, that means that these types are no longer assignment-compatible. Some of the more prominent ones that may affect existing, correct, code are HIObject and ControlRef=HIViewRef. This may require adding typecasts to keep code compiling (the same typecasts are required in C)
+
* '''Old behaviour:''' When the bounds rect was calculated for a text, invisible characters (spaces) and character bearings (spacing around character) were ignored. The result of Canvas.TextExtent() was too short and did not include all with Canvas.TextOut() painted pixels.
−
* '''Changes:''' (apart from the opaque type changes)
+
* '''New behaviour:''' the bounds rect includes invisible characters and bearings. Canvas.TextExtent() covers the Canvas.TextOut() area.
−
** CGGLContextCreate : fixed first parameter (was "var", now is value parameter)
+
* '''Reason for change:''' The text could not be correctly aligned to center or right, the underline and textrect fill could not be correctly painted.
−
** CFHostGetAddressing: var hasBeenResolved: boolean -> booleanptr because can be nil
+
* '''svn''': 49629
−
** CFHostGetNames: var hasBeenResolved: boolean -> booleanptr because can be nil
 
−
** ColorSyncIterateInstalledProfiles: var seed: UInt32 -> UInt32Ptr because can be nil
 
−
** AudioStreamGetPropertyInfo: outSize and outWritable changed to pointer because can be nil
 
−
** cblas (several var-parametes changed to pointers because they represent arrays):
 
−
*** cblas_sswap, cblas_dswap: X, Y
 
−
*** cblas_scopy, cblas_dcopy: Y
 
−
*** cblas_saxpy, cblas_daxpy: Y
 
−
*** catlas_saxpby, catlas_daxpby: Y
 
−
*** catlas_sset, catlas_dset: X
 
−
*** cblas_sscal, cblas_dscal: X
 
−
*** cblas_sgemv, cblas_dgemv: X
 
−
*** cblas_strmv, cblas_dtrmv: X
 
−
*** cblas_stbmv, cblas_dtbmv: X
 
−
*** cblas_stpmv, cblas_dtpmv: Ap, X
 
−
*** cblas_strsv, cblas_dtrsv: X
 
−
*** cblas_stbsv, cblas_dtbsv: X
 
−
*** cblas_stpsv, cblas_dtpsv: Ap, X
 
−
*** cblas_ssymv, cblas_dsymv: X
 
−
*** cblas_ssbmv, cblas_dsbmv: Y
 
−
*** cblas_sspmv, cblas_dspmv: Ap, Y
 
−
*** cblas_sger, cblas_dger: A
 
−
*** cblas_ssyr, cblas_dsyr: A
 
−
*** cblas_sspr, cblas_dspr: Ap
 
−
*** cblas_ssyr2, cblas_dsyr2: A
 
−
*** cblas_sspr2, cblas_dspr2: A
 
−
*** cblas_sgemm, cblas_sgemm: C
 
−
*** cblas_ssymm, cblas_Dsymm: C
 
−
*** cblas_ssyrk, cblas_dsyrk: C
 
−
*** cblas_ssyr2k, cblas_dsyr2k: C
 
−
*** cblas_strmm, cblas_dtrmm: B
 
−
*** cblas_strsm, cblas_strsm: B
 
−
** vBLAS (idem)
 
−
*** SDOT: X, Y
 
−
*** SNRM2: X
 
−
*** SASUM: X
 
−
*** ISAMAX: X
 
−
*** SSWAP: X, Y
 
−
*** SCOPY: X, Y
 
−
*** SAXPY: X, Y
 
−
*** SROT: X, Y
 
−
*** SSCAL: X
 
−
*** SGEMV, A, X, Y
 
−
*** SGEMM: A, B, C
 
−
** vDSP (idem)
 
−
*** vDSP_sve_svesq, vDSP_sve_svesqD: __vDSP_A
 
−
*** vDSP_normalize, vDSP_normalizeD: __vDSP_A, __vDSP_C
 
  
−
== Windows/x86_64 ==
+
==== Generics.Collections & Generics.Defaults ====
 +
* '''Old behaviour:''' Various methods had '''constref''' parameters.
 +
* '''New behaviour:''' '''constref''' parameters were changed to '''const''' parameters.
 +
* '''Reason for change:'''
 +
** Delphi compatibility
 +
** Better code generation especially for types that are smaller or equal to the ''Pointer'' size.
 +
* '''Remedy:''' Adjust parameters of method pointers or virtual methods.
 +
* '''git''': [https://gitlab.com/freepascal.org/fpc/source/-/commit/693491048bf2c6f9122a0d8b044ad0e55382354d 69349104]
  
−
=== Exception handling has been changed to be ABI-conformant  ===
+
== AArch64/ARM64 ==
 +
=== ''{''-style comments no longer supported in assembler blocks ===
 +
* '''Old behaviour''': The ''{'' character started a comment in assembler blocks, like in Pascal
 +
* '''New behaviour''': The ''{'' character now has a different meaning in the AArch64 assembler reader, so it can no longer be used to start comments.
 +
* '''Reason for change''': Support has been added for register sets in the AArch64 assembler reader (for the ld1/ld2/../st1/st2/... instructions), which also start with ''{''.
 +
* '''Remedy''': Use ''(*'' or ''//'' to start comments
 +
* '''svn''': 47116
  
−
* '''Old behaviour''': Exceptions were handled using platform-independent mechanism based on SetJmp/LongJmp.
 
−
* '''New behaviour''': Exceptions are handled using OS-provided means. The most important differences from generic handling are as follows:
 
−
** Every executable contains a <tt>.pdata</tt> section describing layout of function stack frames. This data is used to perform stack back-tracing. As a consequence, the backtraces generated when exception occurs are no longer dependent of code optimization settings. However, they may be different from ones produced by gdb.
 
−
** GNU binutils have troubles creating executables with <tt>.pdata</tt> sections. In particular, ld version < 2.22 crashes at such executables, and using GNU as together with internal linker will strip all <tt>.pdata</tt>, resulting in a non-working executable.
 
−
** An exception is handled in two phases. First phase determines the target frame (i.e. the 'except' statement that will handle the exception), the second phase does actual stack unwinding and executing code in 'finally' statements. In contrast, the generic mechanism is single-phase: it starts unwinding immediately and proceeds until an 'except' statement handles the exception or the stack runs out.
 
−
* '''Reason''': Multiple compatibility issues with Windows and third-party DLLs (see http://bugs.freepascal.org/view.php?id=12974 and related issues)
 
−
* '''Remedy''': No changes are necessary unless your code relies on specific exception handling details. Build programs using FPC's internal assembler and linker, do not use GNU binutils. The entire feature can be disabled by cycling the compiler with <tt>OPT=-dDISABLE_WIN64_SEH</tt> in command line.
 
  
−
== Other ==  
+
== Darwin/iOS ==
  
−
=== Stabs support has been disabled for 64 bit targets ===
+
== Previous release notes ==
−
* '''Old behaviour''': While the default debug information format for 64 bit targets was DWARF (except for AIX, where it's Stabx), it was possible to switch it to Stabs via the -gs command line parameter.
+
{{Navbar Lazarus Release Notes}}
−
* '''New behaviour''': Only the DWARF debug format is still supported on 64 bit targets (except for AIX, where Stabx is used).
 
−
* '''Reason''': Stabs is not well-defined for 64 bit targets, nor well-supported by gdb on those same targets. This can lead to [http://bugs.freepascal.org/view.php?id=23365 problems]
 
−
* '''Remedy''': Do not use -gs when compiling for 64 bit targets. If you do so anyway, the compiler will display a warning and keep the previously set (supported) debug format.
 
  
−
== See also ==
 
−
* [[FPC New Features Trunk]]
 
 
[[Category:FPC User Changes by release]]
 
[[Category:FPC User Changes by release]]
 +
[[Category:Release Notes]]
 +
[[Category:Troubleshooting]]

Latest revision as of 18:32, 9 February 2024

About this page

Listed below are intentional changes made to the FPC compiler (trunk) since the previous release that may break existing code. The list includes reasons why these changes have been implemented, and suggestions for how you might adapt your code if you find that previously working code has been adversely affected by these recent changes.

The list of new features that do not break existing code can be found here.

Please add revision numbers to the entries from now on. This facilitates moving merged items to the user changes of a release.

All systems

Language Changes

Precedence of the IS operator changed

  • Old behaviour: The IS operator had the same precedence as the multiplication, division etc. operators.
  • New behaviour: The IS operator has the same precedence as the comparison operators.
  • Reason: Bug, see [1].
  • Remedy: Add parenthesis where needed.

Visibilities of members of generic specializations

  • Old behaviour: When a generic is specialized then visibility checks are handled as if the generic was declared in the current unit.
  • New behaviour: When a generic is specialized then visibility checks are handled according to where the generic is declared.
  • Reason: Delphi-compatibility, but also a bug in how visibilities are supposed to work.
  • Remedy: Rework your code to adhere to the new restrictions.

Implementation Changes

Disabled default support for automatic conversions of regular arrays to dynamic arrays

  • Old behaviour: In FPC and ObjFPC modes, by default the compiler could automatically convert a regular array to a dynamic array.
  • New behaviour: By default, the compiler no longer automatically converts regular arrays to dynamic arrays in any syntax mode.
  • Reason: When passing a dynamic array by value, modifications to its contents by the callee are also visible on the caller side. However, if an array is implicitly converted to a dynamic array, the result is a temporary value and hence changes are lost. This issue came up when adding TStream.Read() overloads.
  • Remedy: Either change the code so it no longer assigns regular arrays to dynamic arrays, or add {$modeswitch arraytodynarray}
  • Example: this program demonstrates the issue that appeared with the TStream.Read() overloads that were added (originally, only the the version with the untyped variable existed)
{$mode objfpc}
type
  tdynarray = array of byte;

procedure test(var arr); overload;
begin
  pbyte(arr)[0]:=1;
end;

procedure test(arr: tdynarray); overload;
begin
  test[0]:=1;
end;

var
  regulararray: array[1..1] of byte;
begin
  regulararray[1]:=0;
  test(arr);
  writeln(arr[0]); // writes 0, because it calls test(tdynarr)
end.
  • svn: 42118

Directive clause […] no longer useable with modeswitch PrefixedAttributes

  • Old behaviour: A function/procedure/method or procedure/method variable type could be followed by a directive clause in square brackets ([…]) that contains the directives for the routine or type (e.g. calling convention).
  • New behaviour: If the modeswitch PrefixedAttributes is enabled (which is the default in modes Delphi and DelphiUnicode) the directive clause in square brackets is no longer allowed.
  • Reason: As custom attributes are bound to a type/property in a way that looks ambiguous to a directive clause and this ambiguity is not easily solved in the parser it is better to disable this feature.
  • Remedy:
    • don't set (in non-Delphi modes) or disable modeswitch PrefixedAttributes (in Delphi modes) if you don't use attributes ({$modeswitch PrefixedAttributes-})
    • rework your directive clause:
// this
procedure Test; cdecl; [public,alias:'foo']
begin
end;

// becomes this
procedure Test; cdecl; public; alias:'foo';
begin
end;
  • svn: 42402

Type information contains reference to attribute table

  • Old behavior: The first field of the data represented by TTypeData is whatever the sub branch of the case statement for the type contains.
  • New behavior: The first field of the data represented by TTypeData is a reference to the custom attributes that are attributed to the type, only then the type specific fields follow.
  • Reason: Any type can have attributes, so it make sense to provide this is a common location instead of having to parse the different types.
  • Remedy:
    • If you use the records provided by the TypInfo unit no changes should be necessary (same for the Rtti unit).
    • If you directly access the binary data you need handle an additional Pointer field at the beginning of the TTypeData area and possibly correct the alignment for platforms that have strict alignment requirements (e.g. ARM or M68k).
  • svn: 42375

Explicit values for enumeration types are limited to low(longint) ... high(longint)

  • Old behavior: The compiler accepted every integer value as explicit enumeration value. The value was silently reduced to the longint range if it fell outside of that range
  • New behavior: The compiler throws an error (FPC mode) or a warning (Delphi mode) if an explicit enumeration value lies outside the longint range.
  • Reason: Type TEnum = (a = $ffffffff); resulted in an enum with size 1 instead of 4 as would be expected, because $ffffffff was interpreted as "-1".
  • Remedy: Add Longint typecasts to values outside the valid range of a Longint.

Comp as a type rename of Int64 instead of an alias

  • Old behavior: On non-x86 as well as Win64 the Comp type is declared as an alias to Int64 (Comp = Int64).
  • New behavior: On non-x86 as well as Win64 the Comp type is declared as a type rename of Int64 (Comp = type Int64).
  • Reason:
    • This allows overloads of Comp and Int64 methods/functions
    • This allows to better detect properties of type Comp
    • Compatibility with Delphi for Win64 which applied the same reasoning
  • Remedy: If you relied on Comp being able to be passed to Int64 variables/parameters either include typecasts or add overloads for Comp.
  • svn: 43775

Routines that only differ in result type

  • Old behaviour: It was possible to declare routines (functions/procedures/methods) that only differ in their result type.
  • New behaviour: It is no longer possible to declare routines that only differ in their result type.
  • Reason: It makes no sense to allow this as there are situations where the compiler will not be able to determine which function to call (e.g. a simple call to a function Foo without using the result).
  • Remedy: Correctly declare overloads.
  • Notes:
    • As the JVM allows covariant interface implementations such overloads are still allowed inside classes for the JVM target.
    • Operator overloads (especially assignment operators) that only differ in result type are still allowed.
  • svn: 45973

Open Strings mode enabled by default in mode Delphi

  • Old behaviour: The Open Strings feature (directive $OpenStrings or $P) was not enabled in mode Delphi.
  • New behaviour: The Open Strings feature (directive $OpenStrings or $P) is enabled in mode Delphi.
  • Reason: Delphi compatibility.
  • Remedy: If you have assembly routines with a var parameter of type ShortString then you also need to handle the hidden High parameter that is added for the Open String or you need to disable Open Strings for that routine.
  • git: 188cac3b

Unit changes

System - TVariantManager

  • Old behaviour: TVariantManager.olevarfromint has a source parameter of type LongInt.
  • New behaviour: TVariantManager.olevarfromint has a source parameter of type Int64.
  • Reason for change: 64-bit values couldn't be correctly converted to an OleVariant.
  • Remedy: If you implemented your own variant manager then adjust the method signature and handle the range parameter accordingly.
  • svn: 41570

System - buffering of output to text files

  • Old behaviour: Buffering was disabled only for output to text files associated with character devices (Linux, BSD targets, OS/2), or for output to Input, Output and StdErr regardless of their possible redirection (Win32/Win64, AIX, Haiku, BeOS, Solaris).
  • New behaviour: Buffering is disabled for output to text files associated with character devices, pipes and sockets (the latter only if the particular target supports accessing sockets as files - Unix targets).
  • Reason for change: The same behaviour should be ensured on all supported targets whenever possible. Output to pipes and sockets should be performed immediately, equally to output to character devices (typically console) - in case of console users may be waiting for the output, in case of pipes and sockets some other program is waiting for this output and buffering is not appropriate. Seeking is not attempted in SeekEof implementation for files associated with character devices, pipes and sockets, because these files are usually not seekable anyway (instead, reading is performed until the end of the input stream is reached).
  • Remedy: Buffering of a particular file may be controlled programmatically / changed from the default behaviour if necessary. In particular, perform TextRec(YourTextFile).FlushFunc:=nil immediately after opening the text file (i.e. after calling Rewrite or after starting the program in case of Input, Output and StdErr) and before performing any output to this text to enable buffering using the default buffer, or TextRec(YourTextFile).FlushFunc:=TextRec(YourTextFile).FileWriteFunc to disable buffering.
  • svn: 46863

System - type returned by BasicEventCreate on Windows

  • Old behaviour: BasicEventCreate returns a pointer to a record which contains the Windows Event handle as well as the last error code after a failed wait. This record was however only provided in the implementation section of the System unit.
  • New behaviour: BasicEventCreate returns solely the Windows Event handle.
  • Reason for change: This way the returned handle can be directly used in the Windows Wait*-functions which is especially apparent in TEventObject.Handle.
  • Remedy: If you need the last error code after a failed wait, use GetLastOSError instead.
  • svn: 49068

System - Ref. count of strings

  • Old behaviour: Reference counter of strings was a SizeInt
  • New behaviour: Reference counter of strings is now a Longint on 64 Bit platforms and SizeInt on all other platforms.
  • Reason for change: Better alignment of strings
  • Remedy: Call System.StringRefCount instead of trying to access the ref. count field by pointer operations or other tricks.
  • git: ee10850a57

System.UITypes - function TRectF.Union changed to procedure

  • Old behaviour: function TRectF.Union(const r: TRectF): TRectF;
  • New behaviour: procedure TRectF.Union(const r: TRectF);
  • Reason for change: Delphi compatibility and also compatibility with TRect.Union
  • Remedy: Call class function TRectF.Union instead.
  • git: 5109f0ba

64-bit values in OleVariant

  • Old behaviour: If a 64-bit value (Int64, QWord) is assigned to an OleVariant its type is varInteger and only the lower 32-bit are available.
  • New behaviour: If a 64-bit value (Int64, QWord) is assigned to an OleVariant its type is either varInt64 or varQWord depending on the input type.
  • Reason for change: 64-bit values weren't correctly represented. This change is also Delphi compatible.
  • Remedy: Ensure that you handle 64-bit values correctly when using OleVariant.
  • svn: 41571

Classes TCollection.Move

  • Old behaviour: If a TCollection.Descendant called Move() this would invoke System.Move.
  • New behaviour: If a TCollection.Descendant called Move() this invokes TCollection.Move.
  • Reason for change: New feature in TCollection: move, for consistency with other classes.
  • Remedy: prepend the Move() call with the system unit name: System.move().
  • svn: 41795

Math Min/MaxSingle/Double

  • Old behaviour: MinSingle/MaxSingle/MinDouble/MaxDouble were set to a small/big value close to the smallest/biggest possible value.
  • New behaviour: The constants represent now the smallest/biggest positive normal numbers.
  • Reason for change: Consistency (this is also Delphi compatibility), see https://gitlab.com/freepascal.org/fpc/source/-/issues/36870.
  • Remedy: If the code really depends on the old values, rename them and use them as renamed.
  • svn: 44714

Random generator

  • Old behaviour: FPC uses a Mersenne twister generate random numbers
  • New behaviour: Now it uses Xoshiro128**
  • Reason for change: Xoshiro128** is faster, has a much smaller memory footprint and generates better random numbers.
  • Remedy: When using a certain randseed, another random sequence is generated, but as the PRNG is considered as an implementation detail, this does not hurt.
  • git: 91cf1774

Types.TPointF.operator *

  • Old behaviour: for a, b: TPointF, a * b is a synonym for a.DotProduct(b): it returns a single, scalar product of two input vectors.
  • New behaviour: a * b does a component-wise multiplication and returns TPointF.
  • Reason for change: Virtually all technologies that have a notion of vectors use * for component-wise multiplication. Delphi with its System.Types is among these technologies.
  • Remedy: Use newly-introduced a ** b, or a.DotProduct(b) if you need Delphi compatibility.
  • git: f1e391fb

CocoaAll

CoreImage Framework Linking
  • Old behaviour: Starting with FPC 3.2.0, the CocoaAll unit linked caused the CoreImage framework to be linked.
  • New behaviour: The CocoaAll unit no longer causes the CoreImage framework to be linked.
  • Reason for change: The CoreImage framework is not available on OS X 10.10 and earlier (it's part of QuartzCore there, and does not exist at all on some even older versions).
  • Remedy: If you use functionality that is only available as part of the separate CoreImage framework, explicitly link it in your program using the {$linkframework CoreImage} directive.
  • svn: 45767

DB

TMSSQLConnection uses TDS protocol version 7.3 (MS SQL Server 2008)
  • Old behaviour: TMSSQLConnection used TDS protocol version 7.0 (MS SQL Server 2000).
  • New behaviour: TMSSQLConnection uses TDS protocol version 7.3 (MS SQL Server 2008).
  • Reason for change: native support for new data types introduced in MS SQL Server 2008 (like DATE, TIME, DATETIME2). FreeTDS client library version 0.95 or higher required.
  • svn: 42737
DB.TFieldType: new types added
  • Old behaviour: .
  • New behaviour: Some of new Delphi field types were added (ftOraTimeStamp, ftOraInterval, ftLongWord, ftShortint, ftByte, ftExtended) + corresponding classes TLongWordField, TShortIntField, TByteField; Later were added also ftSingle and TExtendedField, TSingleField
  • Reason for change: align with Delphi and open space for support of short integer and unsigned integer data types
  • svn: 47217, 47219, 47220, 47221; git: c46b45bf

DaemonApp

TDaemonThread
  • Old behaviour: The virtual method TDaemonThread.HandleControlCode takes a single DWord parameter containing the control code.
  • New behaviour: The virtual method TDaemonThread.HandleControlCode takes three parameters of which the first is the control code, the other two are an additional event type and event data.
  • Reason for change: Allow for additional event data to be passed along which is required for comfortable handling of additional control codes provided on Windows.
  • svn: 46327
TDaemon
  • Old behaviour: If an event handler is assigned to OnControlCode then it will be called if the daemon receives a control code.
  • New behaviour: If an event handler is assigned to OnControlCodeEvent and that sets the AHandled parameter to True then OnControlCode won't be called, otherwise it will be called if assigned.
  • Reason for change: This was necessary to implement the handling of additional arguments for control codes with as few backwards incompatible changes as possible.
  • svn: 46327

FileInfo

  • Old behaviour: The FileInfo unit is part of the fcl-base package.
  • New behaviour: The FileInfo unit is part of the fcl-extra package.
  • Reason for change: Breaks up a cycle in build dependencies after introducing a RC file parser into fcl-res. This should only affect users that compile trunk due to stale PPU files in the old location or that use a software distribution that splits the FPC packages (like Debian).
  • svn: 46392

Sha1

  • Old behaviour: Sha1file silently did nothing on file not found.
  • New behaviour: sha1file now raises sysconst.sfilenotfound exception on fle not found.
  • Reason for change: Behaviour was not logical, other units in the same package already used sysutils.
  • svn: 49166

Image

FreeType: include bearings and invisible characters into text bounds
  • Old behaviour: When the bounds rect was calculated for a text, invisible characters (spaces) and character bearings (spacing around character) were ignored. The result of Canvas.TextExtent() was too short and did not include all with Canvas.TextOut() painted pixels.
  • New behaviour: the bounds rect includes invisible characters and bearings. Canvas.TextExtent() covers the Canvas.TextOut() area.
  • Reason for change: The text could not be correctly aligned to center or right, the underline and textrect fill could not be correctly painted.
  • svn: 49629

Generics.Collections & Generics.Defaults

  • Old behaviour: Various methods had constref parameters.
  • New behaviour: constref parameters were changed to const parameters.
  • Reason for change:
    • Delphi compatibility
    • Better code generation especially for types that are smaller or equal to the Pointer size.
  • Remedy: Adjust parameters of method pointers or virtual methods.
  • git: 69349104

AArch64/ARM64

{-style comments no longer supported in assembler blocks

  • Old behaviour: The { character started a comment in assembler blocks, like in Pascal
  • New behaviour: The { character now has a different meaning in the AArch64 assembler reader, so it can no longer be used to start comments.
  • Reason for change: Support has been added for register sets in the AArch64 assembler reader (for the ld1/ld2/../st1/st2/... instructions), which also start with {.
  • Remedy: Use (* or // to start comments
  • svn: 47116


Darwin/iOS

Previous release notes

Lazarus - Release Notes and GIT Branch with Release Fixes

Release notes for Version:

0.9.24 | 0.9.26 | 0.9.28 | 0.9.28.2 | 0.9.30 | 1.0 | 1.2 | 1.4 | 1.6 | 1.8 | 2.0 | 2.2 | 3.0 | 4.0

Fixes branch (How to merge):

0.9 | 1.0 | 1.2 | 1.4 | 1.6 | 1.8 | 2.0 | 2.2 | 3.0

Free Pascal Compiler - User Changes (Release Notes)
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