Support constant true and false values in conditions.

[simgear.git] / simgear / compiler.h

diff --git a/simgear/compiler.h b/simgear/compiler.h
index 7d2e6da572995c0ec59253d6bbdd9ea5b234e360..939d9f319c6ad18b2942f7125ebd7fc6504688e4 100644 (file)
--- a/simgear/compiler.h
+++ b/simgear/compiler.h
@@ -63,6 +63,9 @@
 #  if _MSC_VER >= 1200  // msvc++ 6.0 or greater
 #    define isnan _isnan
 #    define snprintf _snprintf
+#    if _MSC_VER < 1500
+#      define vsnprintf _vsnprintf
+#    endif
 #    define copysign _copysign
 
 #    pragma warning(disable: 4786) // identifier was truncated to '255' characters
@@ -131,9 +134,31 @@
 //
 
 #ifdef __APPLE__
+#  ifdef __GNUC__
+#    if ( __GNUC__ > 3 ) || ( __GNUC__ == 3 && __GNUC_MINOR__ >= 3 )
 inline int (isnan)(double r) { return !(r <= 0 || r >= 0); }
-#else
+#    else
+    // any C++ header file undefines isinf and isnan
+    // so this should be included before <iostream>
+    // the functions are STILL in libm (libSystem on mac os x)
+extern "C" int (isnan)(double);
+extern "C" int (isinf)(double);
+#    endif
+#  else
+inline int (isnan)(double r) { return !(r <= 0 || r >= 0); }
+#  endif
+#endif
 
+#if defined (__FreeBSD__)
+#  if __FreeBSD_version < 500000
+     extern "C" {
+       inline int isnan(double r) { return !(r <= 0 || r >= 0); }
+     }
+#  endif
+#endif
+
+#if defined (__CYGWIN__)
+#  include <ieeefp.h>          // isnan
 #endif
 
 
@@ -141,10 +166,5 @@ inline int (isnan)(double r) { return !(r <= 0 || r >= 0); }
 // No user modifiable definitions beyond here.
 //
 
-/** \def SG_USING_STD(x)
- *  Expands to using std::X
- */
-#  define SG_USING_STD(X) using std::X
-
 #endif // _SG_COMPILER_H