Don't configure HAVE_SSE2.

Don't configure HAVE_SSE2 (on behalf of SFMT), because its dependencies
are notoriously unportable in practice.

This resolves #119.

configure.ac

@@ -206,8 +206,6 @@ AC_CANONICAL_HOST
 dnl CPU-specific settings.
 CPU_SPINWAIT=""
 case "${host_cpu}" in
-  i[[345]]86)
-	;;
   i686|x86_64)
 	JE_COMPILABLE([pause instruction], [],
 	              [[__asm__ volatile("pause"); return 0;]],
@@ -215,14 +213,6 @@ case "${host_cpu}" in
 	if test "x${je_cv_pause}" = "xyes" ; then
 	    CPU_SPINWAIT='__asm__ volatile("pause")'
 	fi
-	dnl emmintrin.h fails to compile unless MMX, SSE, and SSE2 are
-	dnl supported.
-	JE_COMPILABLE([SSE2 intrinsics], [
-#include <emmintrin.h>
-], [], [je_cv_sse2])
-	if test "x${je_cv_sse2}" = "xyes" ; then
-	  AC_DEFINE_UNQUOTED([HAVE_SSE2], [ ])
-	fi
 	;;
   powerpc)
 	AC_DEFINE_UNQUOTED([HAVE_ALTIVEC], [ ])

test/include/test/jemalloc_test_defs.h.in

@@ -1,6 +1,9 @@
 #include "jemalloc/internal/jemalloc_internal_defs.h"
 #include "jemalloc/internal/jemalloc_internal_decls.h"
 
-/* For use by SFMT. */
+/*
+ * For use by SFMT.  configure.ac doesn't actually define HAVE_SSE2 because its
+ * dependencies are notoriously unportable in practice.
+ */
 #undef HAVE_SSE2
 #undef HAVE_ALTIVEC