- Delphi (in contrast to C/C++) handles floating-point multiplications with NaN or divisions by 0.0 as floating-point exceptions (FPE). This is a problem with some libraries which expect that e.g. "NaN * 3.0" is NaN or "4.0 / 0" is INFINITY.

- The (strange) default behavior can be changed by setting the control word of the FPU. This is done by assigning $133F to this register via Set8087CW() in delphi. In FPC it was not available for a long time but now it is. OpenGL12.pas contained an own version of Set8087CW() which was totally wrong because the important asm-directives (fclex and fldcw) were missing so it was not of any use. Hence it was removed from the unit so it does not hide the correct FPC version anymore. 
- This should fix some EDivByZero exceptions in floating-point expressions (as with projectM).


git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/trunk@962 b956fd51-792f-4845-bead-9b4dfca2ff2c

1 files changed, 11 insertions, 17 deletions

diff --git a/Game/Code/lib/JEDI-SDL/OpenGL/Pas/opengl12.pas b/Game/Code/lib/JEDI-SDL/OpenGL/Pas/opengl12.pas
index f75b6888..dd27bfbc 100644
--- a/Game/Code/lib/JEDI-SDL/OpenGL/Pas/opengl12.pas
+++ b/Game/Code/lib/JEDI-SDL/OpenGL/Pas/opengl12.pas
@@ -7125,16 +7125,15 @@ end;
 

 //----------------------------------------------------------------------------------------------------------------------

 

-{$ifndef VER140}

+// RaiseLastOSError did not exist in Delphi 5

+{$ifdef VER130}

 

 procedure RaiseLastOSError;

 begin

-  {$ifndef FPC}

   RaiseLastWin32Error;

-  {$endif}

 end;

 

-{$endif VER140}

+{$endif}

 

 //----------------------------------------------------------------------------------------------------------------------

 

@@ -9948,21 +9947,16 @@ begin
 end; 

 

 //----------------------------------------------------------------------------------------------------------------------

-{$ifdef FPC}

-const Default8087CW: Word = $1332;

-

-{$ASMMODE INTEL}

-procedure Set8087CW(NewCW: Word); Assembler;

-asm

-  MOV Default8087CW, AX

-end;

-{$endif}

-

-//----------------------------------------------------------------------------------------------------------------------

 

 initialization

-  ContextList := TThreadList.Create; 

-  Set8087CW($133F); 

+  ContextList := TThreadList.Create;

+  {$IF Defined(CPU386) or Defined(CPUI386) or Defined(CPUX86_64)}

+  // FPC has its own implementation of Set8087CW now. The wrongly

+  // coded (the important asm-directives were missing so it was not of any use!!!)

+  // implementation was removed from this unit so it does not hide the correct FPC version anymore.

+  // This should fix some EDivByZero exceptions in floating-point expressions.

+  Set8087CW($133F);

+  {$IFEND}

 finalization

   CloseOpenGL; 

   ContextList.Free;