- The x87 precision control is now explicitly set for double precision, since

GCC defaults to extended precision instead, unlike Visual C++.
- Removed the useless src/Linux directory from the repository. This was a
  holdover from the long-gone 1.22 build system.



SVN r1118 (trunk)

src/CMakeLists.txt

@@ -116,6 +116,12 @@ else( WIN32 )
 	if( NO_GTK )
 		add_definitions( -DNO_GTK=1 )
 	endif( NO_GTK )
+	
+	find_path( FPU_CONTROL_DIR fpu_control.h )
+	if( FPU_CONTROL_DIR )
+		include_directories( ${FPU_CONTROL_DIR} )
+		add_definitions( -DHAVE_FPU_CONTROL )
+	endif( FPU_CONTROL_DIR )
 endif( WIN32 )
 
 if( X64 )

src/d_main.cpp

@@ -31,7 +31,12 @@
 #define mkdir(a,b) _mkdir (a)
 #else
 #include <sys/stat.h>
-#endif
+#endif
+
+#ifdef HAVE_CPU_CONTROL
+#include <fpu_control.h>
+#endif
+#include <float.h>
 
 #ifdef unix
 #include <unistd.h>
@@ -2068,6 +2073,19 @@ void D_DoomMain (void)
 	const IWADInfo *iwad_info;
 
 	srand(I_MSTime());
+
+	// Set the FPU precision to 53 significant bits. This is the default
+	// for Visual C++, but not for GCC, so some slight math variances
+	// might crop up if we leave it alone.
+#if defined(_FPU_GETCW)
+	{
+		int cw;
+		_FPU_GETCW(cw);
+		_FPU_SETCW((cw & ~_FPU_EXTENDED) | _FPU_DOUBLE);
+	}
+#elif defined(_PC_53)
+	_control87(_PC_53, _MCW_PC);
+#endif
 
 	PClass::StaticInit ();
 	atterm (C_DeinitConsole);