Fixed Altivec support on Mac OS X.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%401178

configure.in

@@ -1922,14 +1922,15 @@ CheckUSBHID()
 dnl Check for altivec instruction support using gas syntax
 CheckAltivec()
 {
-    dnl FIXME: Theoretically, you might not have altivec.h, we should check
+    have_altivec_h_hdr=no
-    dnl FIXME:  that seperately, but I think all major platforms have it
+    AC_CHECK_HEADER(altivec.h, have_altivec_h_hdr=yes)
-    dnl FIXME:  at the moment...  --ryan.
 
     save_CFLAGS="${CFLAGS}"
     have_gcc_altivec=no
     AC_MSG_CHECKING(for Altivec with GCC -maltivec option)
     CFLAGS="${save_CFLAGS} -DGCC_ALTIVEC -DUSE_ALTIVEC_BLITTERS -maltivec"
+
+    if test x$have_altivec_h_hdr = xyes; then
       AC_TRY_COMPILE([
       #include <altivec.h>
       vector unsigned int vzero() {
@@ -1940,12 +1941,8 @@ CheckAltivec()
       have_gcc_altivec=yes
       ])
       AC_MSG_RESULT($have_gcc_altivec)
-
+    else
-    if test x$have_gcc_altivec = xno; then
-        AC_MSG_CHECKING(for Altivec with GCC -faltivec option)
-        CFLAGS="${CFLAGS} -DGCC_ALTIVEC -DUSE_ALTIVEC_BLITTERS -faltivec"
       AC_TRY_COMPILE([
-        #include <altivec.h>
       vector unsigned int vzero() {
           return vec_splat_u32(0);
       }
@@ -1956,8 +1953,39 @@ CheckAltivec()
       AC_MSG_RESULT($have_gcc_altivec)
     fi
 
+    if test x$have_gcc_altivec = xno; then
+        AC_MSG_CHECKING(for Altivec with GCC -faltivec option)
+        CFLAGS="${save_CFLAGS} -DGCC_ALTIVEC -DUSE_ALTIVEC_BLITTERS -faltivec"
+        if test x$have_altivec_h_hdr = xyes; then
+          AC_TRY_COMPILE([
+          #include <altivec.h>
+          vector unsigned int vzero() {
+              return vec_splat_u32(0);
+          }
+          ],[
+          ],[
+          have_gcc_altivec=yes
+          ])
+          AC_MSG_RESULT($have_gcc_altivec)
+        else
+          AC_TRY_COMPILE([
+          vector unsigned int vzero() {
+              return vec_splat_u32(0);
+          }
+          ],[
+          ],[
+          have_gcc_altivec=yes
+          ])
+          AC_MSG_RESULT($have_gcc_altivec)
+        fi
+    fi
+
     if test x$have_gcc_altivec = xno; then
         CFLAGS="${save_CFLAGS}"
+    else
+        if test x$have_altivec_h_hdr = xyes; then
+          CFLAGS="${CFLAGS} -DHAVE_ALTIVEC_H"
+        fi
     fi
 }
 

src/video/SDL_blit_A.c

@@ -422,7 +422,9 @@ static void BlitRGBtoRGBPixelAlphaMMX(SDL_BlitInfo *info)
 #endif
 
 #ifdef USE_ALTIVEC_BLITTERS
+#ifdef HAVE_ALTIVEC_H
 #include <altivec.h>
+#endif
 #include <assert.h>
 
 #if ((defined MACOSX) && (__GNUC__ < 4))

src/video/SDL_blit_N.c

@@ -36,7 +36,9 @@ static char rcsid =
 /* Functions to blit from N-bit surfaces to other surfaces */
 
 #ifdef USE_ALTIVEC_BLITTERS
+#ifdef HAVE_ALTIVEC_H
 #include <altivec.h>
+#endif
 #include <assert.h>
 #include <stdlib.h>
 #ifdef MACOSX