User Changes Trunk
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Revision as of 14:19, 25 February 2012 by Jonas (talk | contribs) (→'Overload'' modifier must be present in the interface)
About this page
Below you can find a list of intentional changes since the 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 here.
All systems
Unit changes
Several methods of TDataset changes signature (TRecordBuffer)
- Old behaviour: Several (virtual) methods of TDataset have parameters of type "pchar", which are often called "buffer".
- New behaviour: The pchar type has been changed to TRecordBuffer. Currently this type is still an alias for p(ansi)char, but in time it will be changed to pbyte for the 2.7.1/2.8.0 branch, which is D2009+ compatible.
- Reason: Preparation for Delphi 2009+ compatibility and improving of general typing. In Delphi 2009+ (and fully compatible FPC modes in the future) pchar is not pointer to byte anymore. This change will be merged back to 2.6(.2), but with TRecordBuffer=pchar.
- Remedy: Change the relevant virtual methods to use TRecordBuffer for buffer parameters. Define TRecordBuffer=pansichar to keep older Delphis and FPCs working.
DLLParam changed from Longint into PtrInt
- Old behaviour: DLLParam was of type Longint even on Win64.
- New behaviour: DLLParam is now of type PtrInt so also on 64 Bit systems.
- Reason: Prevent data loss, match the declaration in the Windows headers.
- Remedy: Change the declaration of the procedures used as dll hook to take a PtrInt parameter instead of Longint.
Language Changes
Overload modifier must be present in the interface
- Old behaviour: It was possible to declare a function/procedure/method as overload only in the implementation.
- New behaviour: If an overload directive is used, it must also appear in the interface.
- Reason: The old mechanism could cause hard to find problems (depending on whether or not the implementation was already parsed, the compiler would treat the routine as if it were declared with/without overload), it could cause unwanted unit recompilations due to interface crc changes, and Delphi compatibility.
- Remedy: Make sure that the overload modifier is present both in the interface and in the implementation if you use it.
