Description: Test for SIMD instructions at run-time only if configured.
 Do not attempt to use e.g. CPU detection if the result does not matter
 anyway; fixes FTBFS on architectures with slightly different asm, such
 as x32.
Author: Thorsten Glaser <t.glaser@tarent.de>
Forwarded: no
Bug-Debian: coming
Last-Update: 2015-08-28

--- a/configure.ac
+++ b/configure.ac
@@ -386,6 +386,8 @@ AC_SUBST(PROGRAM_NOPIC)
 
 if test "$enable_simd_accel" != "false" -a "$enable_simd_accel" != "no"
 then
+  AC_DEFINE(HAVE_SIMD_ACCEL, 1, [use SIMD multimedia instructions if possible])
+
   if test x$have_x86cpu = xtrue
   then
       AC_MSG_CHECKING([if C compiler accepts inline MMX assembly])
--- a/utils/cpu_accel.c
+++ b/utils/cpu_accel.c
@@ -38,7 +38,7 @@
 #include <malloc.h>
 #endif
 
-#ifdef HAVE_ALTIVEC
+#if defined(HAVE_SIMD_ACCEL) && defined(HAVE_ALTIVEC)
 extern int altivec_copy_v0();
 #endif
 
@@ -77,7 +77,7 @@ extern int altivec_copy_v0();
 
 static char *parse_next(char **, const char *);
 
-#ifdef HAVE_X86CPU 
+#if defined(HAVE_SIMD_ACCEL) && defined(HAVE_X86CPU)
 
 /* Some miscelaneous stuff to allow checking whether SSE instructions cause
    illegal instruction errors.
@@ -208,7 +208,7 @@ static int x86_accel (void)
 #endif
 
 
-#ifdef HAVE_ALTIVEC
+#if defined(HAVE_SIMD_ACCEL) && defined(HAVE_ALTIVEC)
 /* AltiVec optimized library for MJPEG tools MPEG-1/2 Video Encoder
  * Copyright (C) 2002  James Klicman <james@klicman.org>
  *
@@ -263,7 +263,7 @@ noAltiVec:
 
 int32_t cpu_accel (void)
 {
-#ifdef HAVE_X86CPU 
+#if defined(HAVE_SIMD_ACCEL) && defined(HAVE_X86CPU)
     static int got_accel = 0;
     static int accel;
 
@@ -273,7 +273,7 @@ int32_t cpu_accel (void)
     }
 
     return accel;
-#elif defined(HAVE_ALTIVEC)
+#elif defined(HAVE_SIMD_ACCEL) && defined(HAVE_ALTIVEC)
     return detect_altivec();
 #else
     return 0;
@@ -356,7 +356,7 @@ void *bufalloc( size_t size )
 
 	if( !bufalloc_init )
 	{
-#ifdef HAVE_X86CPU 
+#if defined(HAVE_SIMD_ACCEL) && defined(HAVE_X86CPU)
 		if( (cpu_accel() &  (ACCEL_X86_SSE|ACCEL_X86_3DNOW)) != 0 )
 		{
 			simd_alignment = 64;