Lazarus Faq

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General

What is Lazarus?

Lazarus is a cross-platform integrated development environment (IDE) that lets you create visual (GUI) and non-visual Object Pascal programs, and uses the Free Pascal compiler to generate your executable. Its aim is write once, compile anywhere: you should be able to just recompile your program source code with Lazarus running on another operating system (or a cross compiler) and get a program that runs on that operating system.

For more details see Overview of Free Pascal and Lazarus

Why are the generated binaries so big?

The binaries are big because they include a lot of debug information necessary for using gdb (GNU Debugger). A debugger is a program that is used to test your code. It uses the extra-information stored in your binary to test it. But once your program is working well, you may delete those infos and reduce the size of the binary.

Quick guide to Lazarus/FPC application size reduction

• 1. Project|Compiler Options|Code|Smart Linkable (-CX) -> Checked
• 2. Project|Compiler Options|Linking|Debugging| Uncheck all except Strip Symbols From Executable (-Xs)

Note: only do this if you don't need to run the debugger. For more details, see Size Matters

Lazarus executable size starts big, but grows very slowly, because of the way the LCL is designed, and its use of certain Free Pascal features (RTTI). Projects that don't use the LCL are much smaller (this is similar to some non-GUI C++ frameworks). This typically requires more manual coding though.

Do I need ppc386.cfg or fpc.cfg?

You only need fpc.cfg. This way the compiler knows where to find the libraries.

How do I compile Lazarus?

Do something like this:

$cd lazarus$ make clean all

If you want to build Lazarus for different widgetset eg. Qt (supported on Linux, Windows and OSX) then use the LCL_PLATFORM argument:

$cd lazarus$ make clean all LCL_PLATFORM=qt

How do I build other projects based upon the LCL without the IDE

If you want to compile projects automatically or from the command line, use lazbuild. This is a command line version of the IDE to build Lazarus projects and packages.

If you want to build LCL applications without the IDE and without lazbuild, add the following lines to the end of your fpc.cfg

# searchpath for other toolkits (Linux)
-Fu/usr/lib/fpc/$fpcversion/units/$fpctarget/{YourToolKit}

# searchpath for other toolkits (Windows)
-Fu/{YourLazarusDirectory}/components/lazutils/lib/{platform}
-Fu/{YourLazarusDirectory}/lcl/units/{platform}
-Fu/{YourLazarusDirectory}/lcl/units/{platform}/{YourToolKit}
Where {YourToolKit} may be gtk2, gnome, qt or win32 and {platform} may be x86_64-linux and run:
ppc386 your.project.pp

Hint: Don't forget to install the development packages for your toolkit otherwise you might receive something like: Linker message: cannot find -l.

What version of FPC is required?

• Lazarus 1.0.8 requires at least FPC 2.6.2.
• Lazarus 1.0 requires at least FPC 2.6.0.

I can't compile Lazarus

1. Check if the compiler is the correct version
2. Check if the (fpc) libraries are from the same version
3. Check if the compiler installation path has spaces in it. Make sure it doesn't!
4. Check if you have a fpc.cfg and no old ppc386.cfg
5. Check also the OS-dependent FAQs
6. If you're still stuck, ask on the forum or Lazarus mailing list

How to embed a small file in the executable, without the need of a separate file? How to embed a resource?

Both Lazarus resource and Windows-type/FPC resources are supported. See Lazarus Resources.

What is the meaning of the various file extensions used by Lazarus?

The Lazarus Tutorial#The Lazarus files explains some extensions by an example. Here is a brief list:

extension filetype description
.lpi Lazarus Project Information contains project-specific settings like compiler settings and needed packages. stored in XML
.lps Lazarus Program Session Personal data like cursor positions, source editor files, personal build modes. stored in XML
.lpr Lazarus Program Pascal source of main program.
.lfm Lazarus Form Form configuration information for all objects on a form (stored in a Lazarus-specific textual format, similar to Delphi fdm; the actions are described by Pascal source code in a corresponding *.pas file)
.pas
.pp
.p
Pascal code Pascal code typically for a form stored in a corresponding *.lfm file
.lrs Lazarus Resource Generated Lazarus Resource file; not to be confused with a Windows resource file.

This file can be created with lazres tool (in directory Lazarus/Tools) using commandline: lazres myfile.lrs myfile.lfm

.ppu Compiled unit Compiled source code created by the Free Pascal compiler for each unit and program.
.o Object file created by the compiler, every ppu file has a corresponding o file, needed by the linker.
.lpk Lazarus package information package-specific settings, like compiler settings and needed packages; stored in XML
.lrt Lazarus Resourcestring table Lazarus Resourcestring table created when saving a lfm file and i18n is enabled. It contains the TTranslateString properties of the lfm. Do not edit them, they are overwritten.
.rst Resourcestring table Resourcestring table created by the compiler for every unit with a resourcestring section. Do not edit them, they are overwritten.
.po gnu gettext messages When i18n is enabled the IDE creates/updated the .po files with the resourcestrings from the rst and lrt files.

Why are TForm.ClientWidth/ClientHeight the same as TForm.Width/Height

The TForm.Width/Height do no include the frame, because there was no way to retrieve the frame size on all platforms. Without a reliable way, the LCL would move the forms around on the screen or resize them endlessly.

Eventually it will be changed when there is a reliable way to get the size and position of a window with its frame on all platforms. To keep compatibility with older LCL forms, a version number and some extra methods will be added.

Errors

Platform specific errors/problems are also covered in sections below.

'Fatal: Circular unit reference between a and b'

A common thing happened to a new user when one wants to create two forms referencing each other's properties. The error above only happens to uses clause of interface section, thus it's OK to put it in implementation section. Example:

This one causes error:

unit a;

interface

uses b;

implementation

end.
unit b;

interface

uses a;

implementation

end.

But this one doesn't:

unit a;

interface

implementation

uses b;

end.
unit b;

interface

implementation

uses a;

end.

In some cases the minimal base class method might be suitable.

Separate one class into a minimal base class (what the other needs) and derive it for the rest of the implementation.

unita: uses unitb

  type
ClassA = class(BaseClassA)
// rest of ClassA
end;

unitb:

  type
ClassB = class;  //forward declaration

BaseClassA = class
// references ClassB
end;

ClassB = class
// references BaseClassA
end;

When I do var mytext: text; to declare a text file, I get "Unit1.pas(32,15) Error: Error in type definition". How can I fix this?

The TControl class has a Text property. In a method of a form, that has higher visibility, the Text type from the system unit. You can use the TextFile type, which is just an alias for the Text type or you can add the unit to the type definition.

var
MyTextFile: TextFile;
MyText: System.Text;

A similar name clash exists with assigning and closing a text file. TForm has a assign and a Close method. You can use AssignFile and CloseFile or add the unit name System.

I get an error when using Printer.BeginDoc

The unit Printers must be added to the uses section.

The Printer4Lazarus package must be added to your project requirement in the IDE under: Project|Project Inspector|Add|New Requirement|Package Name:

If the package Printer4Lazarus package is not in the list when opening the dropdown box it must be installed. The package is part of the Lazarus installation and can be found in: [lazarus installed directory]\components\printers

If you used the default installation directories [lazarus installed directory] is:

• Windows: c:\lazarus
• Linux: /usr/lib/lazarus

The same solution also applies to the exception you can get when referencing Printer.Printers

When I try to compile a project, I get an error message "Cannot find Unit ..."

Please see Unit not found - How to find units

For information on the error "Cannot find unit interfaces", see the next section.

When I try to compile a project, I get an error message "Cannot find Unit interfaces"

This error means that the compiler can not find the file 'interfaces.ppu' or the file was found, but it is wrong or outdated (the .ppu file date code is older than the date code of the compiler itself). Testing the compiler option settings can help debug these issues, via Project: Compiler Options... (use the Test button at the bottom of the dialog). This test also lets you check that the {TargetCPU} and {TargetOS} variables are set properly.

The interfaces unit can be found in {LazarusDir}\lcl\units\{TargetCPU}-{TargetOS}\{LCLWidgetSet}\interfaces.ppu. For example: /home/username/lazarus/lcl/units/i386-linux/gtk/interfaces.ppu.

It is normal to have multiple versions of interfaces.ppu (in the proper directories) to allow compiling with different widgets.

If the interface.ppu file is in the folder matching the OS and CPU you selected in the project preferences, and you get this error, you are using a different compiler / RTL for compiling your project than you used for compiling your Lazarus IDE, or the libraries need to be recompiled to give the .ppu files newer compilation dates.

You can do one of the following:

1. Set the compiler in the Environment Options to the one you used to compile Lazarus. Also look carefully in the Environment Options to see if you are using the correct paths for the Lazarus directory and the FPC sources directory. Check that there is only one version of the compiler configuration file fpc.cfg - it should reside in /etc/ for Linux/Unix systems or in the same directory as the fpc compiler for Windows systems. Try to run "fpc -vt bogus" to check which fpc.cfg is being used in your system. Rogue copies often creep in if you have updated your compiler to a new version; they may be found in your home directory or in the same directory as the one in which you built your new compiler. DELETE THESE!
2. Rebuild the LCL (or Lazarus completely) with the compiler selected in the Environmnent Options. You can do this with Tools -> Build Lazarus. Before doing this, check the current settings in Tools -> Configure Build Lazarus.
3. You may also try to change the widgetset currently selected for the project. For example, the sample project "objectinspector" that comes with Lazarus is set to gtk by default. Compiling this project will surely give you "Can't find unit interfaces" in Windows platform. Changing widgetset to default(Win32) in Project Options | Compiler Options... should fix this issue.

When I compile a project, that uses a LCL unit, I get a linker error

Here is an example for such a linker error:

/path/to/lazarus/lcl/units/x86_64-linux/wsimglist.o: In function REGISTERCUSTOMIMAGELIST':
/path/to/lazarus/lcl//widgetset/wsimglist.pp:266: undefined reference to WSRegisterCustomImageList'

• Make sure yor project uses the package LCL. You can check this in the project inspector.
• Make sure unit "interfaces" is used as one of the first units of your program.

Note: These functions are implemented by the LCL backends. By adding the unit interfaces, you link a LCL backend into your program.

At the line :{$R *.DFM} How can I solve this problem? Lazarus (or better Linux) doesn't know about resources, so you can't use them in the way Delphi/Win32 does. However Lazarus uses a method pretty compatible with this. You can still use your Delphi layouts (.dfm files) if you use the following steps: • You need a textual version of the .dfm files. D5 and higher are doing this by default. If you have older files: Alt+F12 to see the layout as text and paste/copy. When you have a text .dfm file, just copy it to a .lfm file. • Create a file with lazres (in lazarus/tools) lazres yourform.lrs yourform.lfm • Add the following initialization section to initialization {$I yourform.lrs}

Please keep in mind that not all properties in the dfm are supported yet by Lazarus, so you might get a crash.

Edit: Since FPC 2.4.0, Delphi style resources are supported, so you don't need to change anything. Even Lazarus SVN already uses it as default projects. Note: it's still advised that you use Lazarus' Delphi project converter as there might still be unsupported properties.

When creating a form Lazarus automaticaly add some extra units to the uses section of your form unit. During the conversion of a delphi unit to a Lazarus unit this does not happen. So you need to add LResources to the Uses section of your form unit.

When accessing events of objects, e.g., the onclick event of a button, I get the following error. ERROR unit not found: stdCtrls

Make sure, in the Project -> Project Inspector, that your project depends on the package "LCL" and that you have installed the FPC sources.

Lazarus is the IDE and the visual components library LCL. All other stuff, like IO, Database, FCL and RTL are provided by FPC. The IDE needs the paths to all sources.

The FPC source path can be set via: Environment -> Environment Options -> Files -> FPC source directory

'Fatal: Internal error XXXXYYZZW'

An internal error is a compiler error that is not expected to happen (but is prepared to easily track down the problem if happens by giving code XXXXYYZZW). Every internal error is a bug, thus it's advised to report to the bugtracker (with small example that can demonstrate the internal error) when one gets it.

Lazarus cannot open a project if last character of the path to it is a space

If you try to open a project like "/home/bart/space /test.lpi" (note the space just before /test.lpi), the Lazarus IDE will give an error saying it cannot find "/home/bart/space /test.lpi".
This is a known limit of the IDE, which is caused by the fact that the IDE a.o. has to handle paths that users have supplied in edit controls, which have to be stripped from surrounding spaces.
This limitation in no way affects user programs written in Fpc/Lazarus.
Avoid such pathnames for projects.

Debugger

How can I inspect properties?

You have to use FPC 2.4 or newer.

If you compile your application using -gw (dwarf debug info), you should be able to inspect properties.

Note: This is only true for properties that map directly to a variable (the "read" declaration points to a member, not a function).

If your property returns the value of a function it is very dangerous to evaluate/inspect it. It would require this function to be called, and very often it would change the values of some of your variables. This would mean it would alter the state of your application in the debugger, and any further code-execution, debugging or inspections would return incorrect results.

The optional ability to explicitly inspect the results of functions (with the risks described), and therefore calling code from the debugger is not yet implemented

Why does the debugger not show some Variables/Structures ("no such symbol"/"incomplete type")

For problems debugging:

• properties
• Array of ... (Dynamic Array)
• Variables in Nested Procedures
• "no such symbol in context"
• "incomplete type"

Please see GDB Debugger Tips

How can I debug FCL components from packages with Lazarus

FCL components and classes are built without debug information by default and as a result, gdb cannot access component methods or properties. To build package components they must be rebuilt with a debug-line information "-gl" switch.

This example assumes you have a Linux distribution with /usr/local/ installation prefix and that the Database package fcl-db is what is needed to contain debug-line information. While the fcl-db is used in this example, you may issue this make command from ANY of the included packages.

Before you begin, you need to locate your FPC path by examining your FPC configuration file. The file (fpc.cfg) is located at /etc/fpc.cfg. Display the contents of fpc.cfg and find your fpc installation path. Look for a line starting with -Fu in the fpc.cfg:

-Fu/usr/local/lib/fpc/$fpcversion/units/$fpctarget/*


Make scripts are installing units into INSTALL_PATH/lib/fpc/$fpcversion/units/$fpctarget/, so you must be sure that /usr/local is the installation path, and should be assigned to INSTALL_PREFIX, otherwise the Make scripts will place units where they don't belong or the Make script will fail.

Step 1: Open a shell terminal
Step 2: cd /user/local/share/src/fpc-2.3.1/fpc/fcl-db/
Step 3: sudo make clean all install INSTALL_PREFIX=/usr/local OPT=-gl

Note: INSTALL_PREFIX parameter should be properly configured for units to be installed.

In the sample below /usr/local is a default fpc path for Linux, but may vary on other OSes.

make clean all install INSTALL_PREFIX=/usr/local OPT=-gl

Finally, after rebuilding any FCL units you may want to rebuild LCL as well.

How can I use a log file for debugging?

Lazarus provides a basic log framework in the unit LazLogger. See that page for more details.

How can I use a Log-file for debugging the IDE itself?

Lazarus itself uses LazLogger.

This means that you can run Lazarus with
--debug-log=lazarusdebuglog.txt

If this is not sufficient: in the IDE the extent of the information that is logged can be controlled with --debug-enable. See --help for a list of keywords, or install the package IdeLazLogger.

$ddd lazarus Be warned, however, that ddd is not as comfortable as, e.g., the Lazarus debugger, especially if it comes to view the contents of a variable you have to take into account that ddd/gdb are case sensitive whereas Pascal is case-insensitive. Therefore, you have to type all variable names in uppercase to see their contents. For more information see the fpc-manuals. I can debug now but ddd does not find my sources or complains that they contain no code. What's that? This is a path-related problem with either gdb or ddd. You can avoid this by • Use the "Change directory" command from the ddd menu and choose the directory where the sources are located. The drawback of this method is that you now can't use the source of the program you started with (e.g. lazarus). Thus it may be neccessary to change the directory multiple times. • In ddd goto  [gdb-settings] and set the search-path • Create a$(HOME)/.gdbinit file like:
     directory /your/path/to/lazarus
directory /your/path/to/lazarus/lcl
directory /your/path/to/lazarus/lcl/include


I receive an error during the linking that states /usr/bin/ld: cannot find -l<some lib>

For example:

 /usr/bin/ld: cannot find -lgdk


This means an external library was not found. In the above case under Linux it means the libgdk.so or libgdk.a was not found. Normally this means, you forgot to install the development package of this library. In the case of gdk the package is called under the Fedora Core distribution: 'gtk+-devel-1.2.10-33'.

Package Based Distributions
You need to install the package that provides the lib<somelib>.so or lib<somelib>.a files. Dynamic libs under linux have the extension .so, while static libs have the extension .a. On some Linux distro's you have installed the package (rpm, deb) <packagename> which provides <some lib>, but you also need the development package (rpm, deb), normally called <packagename>-dev, which contains the .a (static lib) and/or the .so (dynamic lib).
Some distributions have commands to find which package contains a file:
Mandriva
urpmf lib<somelib>.so
will list all packages containing the file named lib<somelib>.so, you'll have to install those ending in -devel
Debian
install the apt-file utility (apt-get install apt-file) then
apt-file search lib<somelib>.so
will list all packages containing the file named lib<somelib>.so, you'll have to install those ending in -dev
SuSE
SuSE installs the gtk devel libs under /opt/gnome/lib (or /opt/gnome/lib64 for 64 bits), which is not in the standard lib path. Simply add it to your /etc/fpc.cfg. (-Fl/opt/gnome/lib).
Source Based Distributions and Manual Compilation (LFS)
Make sure that there is a lib<somelib>.a in the path, and that it contains the right version. To let the linker find the dynamic library, create a symlink called lib<some lib>.so to lib<some lib><version>-x,y.so if necessary (and/or for static lib; lib<some lib>.a to lib<some lib><version>-x,y.a).
FreeBSD : As source based distro's, and also make sure you have -Fl/usr/local/lib in your fpc.cfg and/or Lazarus library path. Keep in mind that GTK1.2 has "gtk12" as package name under FreeBSD. (same for glib) NOTE: This has changed as of late. Newest ports have gtk-12 and glib-12 as well. You might stumble on this problem, since FPC requires the "-less" ones, you will need to symlink them like this:
# as root
cd /usr/local/lib && ln -s libglib-12.so libglib12.so
cd /usr/X11R6/lib && ln -s libgtk-12.so libgtk12.so
cd /usr/X11R6/lib && ln -s libgdk-12.so libgdk12.so
NetBSD : As source based distro's, and also make sure you have -Fl/usr/pkg/lib in your fpc.cfg and/or Lazarus library path
Fedora : In the "add/remove software" panel search for: "gtk2-devel", "glibc-devel" ([see here]), "libx11-devel"

How can I convert a Kylix 2 project into a Lazarus project?

Nearly the same way as converting a Kylix project into a Delphi/VCL project.

The LCL (Lazarus Component Library) tries to be compatible to Delphi's VCL. Kylix's CLX tries to be QT compatible. Here are some general hints:

• Rename all used CLX Q-units like QForms, QControls, QGraphics, ... into their VCL counterparts: Forms, Controls, Graphics, ...
• Add LResources to the uses section of every form source
• Rename or copy all .xfm files to .lfm files.
• Rename or copy .dpr file to .lpr file.
• Add "Interfaces" to the uses section in the .lpr file.
• Remove {$R *.res} directive • Remove {$R *.xfm} directive
• Add {$mode objfpc}{$H+} or {$mode delphi}{$H+} directive to .pas and .lpr files
• Add an initialization section to the end of each form source and add an include directive for the .lrs file (Lazarus resource file):
initialization
{$I unit1.lrs} The .lrs files can be created via the lazres tool in: (lazarusdir)/tools/lazres. For example: ./lazres unit1.lrs unit1.lfm • Fix the differences. The LCL does not yet support every property of the VCL and the CLX is not fully VCL compatible. • To make it more platform independent, reduce unit libc (which is deprecated) references and substitute with native FPC units like baseunix/unix as much as possible. This will be necessary to support other targets than linux/x86 (including OS X, FreeBSD and Linux/x86_64) When compiling lazarus the compiler can not find a unit. e.g.: gtkint.pp(17,16) Fatal: Can't find unit GLIB 1. Check a clean rebuild: do a 'make clean all' 2. Check if the compiler has the correct version (2.0.4 or higher) 3. Check if the compiler is using the right config file. The normal installation creates /etc/fpc.cfg. But fpc also searches for ~/.ppc386.cfg, ~/.fpc.cfg, /etc/ppc386.cfg and it uses only the first it finds. Hint: You can see which config file is used with 'ppc386 -vt bogus' Remove any ppc386.cfg as it is really obsolete. 4. Check if the config file (/etc/fpc.cfg) contains the right paths to your fpc libs. There must be three lines like this:  -Fu/usr/lib/fpc/$fpcversion/units/$fpctarget -Fu/usr/lib/fpc/$fpcversion/units/$fpctarget/rtl -Fu/usr/lib/fpc/$fpcversion/units/$fpctarget/*  The first part of these paths (/usr/lib/fpc) depends on your system. On some systems this can be for example /usr/local/lib/fpc/... . Hint: You can see your searchpaths with 'ppc386 -vt bogus' 5. Check that the config file (/etc/fpc.cfg) does not contain search paths to the lcl source files (.pp, .pas):  forbidden: -Fu(lazarus_source_directory)/lcl forbidden: -Fu(lazarus_source_directory)/lcl/interfaces/gtk  If you want to add the lcl for all your fpc projects, make sure that the two paths look like the following and are placed after the above fpc lib paths:  -Fu(lazarus_source_directory)/lcl/units/$fpctarget
-Fu(lazarus_source_directory)/lcl/units/$fpctarget/gtk  6. Check if the missing unit (glib.ppu) exists in your fpc lib directory. For example the gtk.ppu can be found in /usr/lib/fpc/$fpcversion/units/i386-linux/gtk/. If it does not exists, the fpc lib is corrupt and should be reinstalled.

7. Check if the sources are in a NFS mounted directory. In some cases the NFS updates created files incorrectly. Please, try to move the sources into a non NFS directory and compile there.

8. If you are still not succeeded try to use samplecfg script as follows:

# cd /usr/lib/fpc/version/

# sudo ./samplecfg /usr/lib/fpc/\$version /etc Note: Do not a slash ("/") after etc, because if you do, the system will create a folder /etc/fpc.cfg/fpc.cfg. In fact, we want samplecfg to make a file /etc/fpc.cfg, not the folder /etc/fpc.cfg. I have installed the binary version, but when compiling a simple project, Lazarus gives: Fatal: Can't find unit CONTROLS Probably you are using a newer fpc package, than that used for building the lazarus binaries. The best solution is to download the sources and compile lazarus manually. You can download the source snapshot or get the source via svn: $ bash
$svn checkout http://svn.freepascal.org/svn/lazarus/trunk lazarus$ cd lazarus
$make clean all Make sure that Lazarus get the new source directory: Environment->General Options->Files->Lazarus Directory Top Lazarus compiles, but linking fails with: libgdk-pixbuf not found Install the gdk-pixbuf library for gtk1.x: Where to find the gdk-pixbuf library: Debian packages: libgdk-pixbuf-dev Ubuntu 8.10: If you are compiling Lazarus with GTK 2.0 you'll get a "libgdk-pixbuf2.0" not found error. Just install libgtk2.0-dev using apt on this way: apt-get install libgtk2.0-dev I have SuSE and I get /usr/bin/ld: cannot find -lgtk Error: Error while linking Older SuSE versions (before SuSE 11) install the gtk devel libs under /opt/gnome/lib (or /opt/gnome/lib64 for 64 bits), which is not in the standard lib path. Simply add it to your /etc/fpc.cfg (-Fl/opt/gnome/lib). I have Kubuntu and I get /usr/bin/ld: cannot find -lgtk-x11-2.0 You can either use the QT or the GTK2 backend. Default is GTK2. For GTK2 install the kubuntu package libgtk2.0-dev. Lazarus crashes with runtime error 211 after I installed a component After I installed a component, Lazarus crashes with the following message: Threading has been used before cthreads was initialized. Make cthreads one of the first units in your uses clause. Runtime error 211 at$0066E188


How can I fix this?

Your freshly installed component is using threads. FPC on *nix doesn't automatically include threading support, but it must be intialized. This initialization is done in the cthreads unit. Every application using the component needs to add this unit to the uses clause of the main program. Lazarus itself is no exception. This can be done in two ways:

1) Open the package. In the package editor click on Options. Under page Usage add to the custom options -dUseCThreads. Then rebuild the IDE. This way the cthreads unit will be automatically used by the IDE under unix and the cthreads are initialized.

2) In order to avoid modifying package, an FPC compiler option could be used directly. Open menu Tools->Configure "build Lazarus". "Configure build Lazarus" dialog will be shown; in field "Options:" type -Facthreads and then press "OK" button. The next step is to install the package. Lazarus will be built with option -Facthreads which means that it will treat main program as if unit cthreads where first in uses clause.

Hint: Maybe your old (non-crashing) Lazarus executable is stored as lazarus.old in the same directory as the crashing Lazarus executable.

When I run a program with threads I get runtime error 232

The complete error message is:

This binary has no thread support compiled in.
Recompile the application with a thread-driver in the program uses
clause before other units using thread.
Runtime error 232


Solution: Add cthreads as first unit to the uses clause of your main program, usually the .lpr-file.

I have Ubuntu Breezy/Mandriva KDE3 and my fonts in Lazarus IDE look too big

If Lazarus is compiled with Gtk1.2, the settings in Gnome Preferences/Font don't have any effect as they are related to Gtk2. You could try this solution: Create a file named .gtkrc.mine in your home directory (if it's not already there) and add these lines to it:

style "default-text" {
fontset = "-*-arial-medium-r-normal--*-100-*-*-*-*-iso8859-1,\
-*-helvetica-medium-r-normal--*-100-*-*-*-*-*-*"
}

class "GtkWidget" style "default-text"


If this is not enough try and create also a .gtkrc symlink to .gtkrc.mine . It worked in this way under Xubuntu 7.10, Mandriva 2009.0 KDE3.

How can my gtk programs use custom rc files?

Option a) Name the rc file yourprogram.gtkrc and put it in the same directory where the executable is.

Antivirus

Excluding the Lazarus directory (and the directory/directories where your project/projects are) from on access virus scanning may help there.