Fix warnings in nedmalloc when compiling with GCC 4.4.0

Nedmalloc's source code has a cute #define construct to avoid inserting
an if() statement, because that might interact badly with enclosing if()
statements.  However, GCC > 4 complains with a "warning: value computed
is not used".  So we cast the result to "void".

GCC also does not understand the Visual C++ specific pragmas, so we need
to disable them for MinGW.

We need to include malloc.h on Windows even if we happen to compile the
stuff as a MinGW program.  Otherwise the function declaration of alloca()
is missing.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

compat/nedmalloc/malloc.c.h

@@ -1270,7 +1270,9 @@ int mspace_mallopt(int, int);
 /*------------------------------ internal #includes ---------------------- */
 
 #ifdef WIN32
+#ifndef __GNUC__
 #pragma warning( disable : 4146 ) /* no "unsigned" warnings */
+#endif
 #endif /* WIN32 */
 
 #include <stdio.h>       /* for printing in malloc_stats */
@@ -2541,7 +2543,7 @@ struct malloc_params {
 static struct malloc_params mparams;
 
 /* Ensure mparams initialized */
-#define ensure_initialization() (mparams.magic != 0 || init_mparams())
+#define ensure_initialization() ((void)(mparams.magic == 0 || init_mparams()))
 
 #if !ONLY_MSPACES
 

compat/nedmalloc/nedmalloc.c

@@ -34,7 +34,7 @@ DEALINGS IN THE SOFTWARE.
 /*#define FULLSANITYCHECKS*/
 
 #include "nedmalloc.h"
-#if defined(WIN32) && !defined(__MINGW32__)
+#if defined(WIN32)
  #include <malloc.h>
 #endif
 #define MSPACES 1