From 9f9240b661c5f381831b62d72b6ea928a91ff43a Mon Sep 17 00:00:00 2001
From: Wayne Davison <wayne@opencoder.net>
Date: Thu, 3 Sep 2020 10:07:36 -0700
Subject: [PATCH] Set CXX_OK=no when cross compiling.

---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 64d2e6d6..109546a6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -233,7 +233,7 @@ __attribute__ ((target("ssse3"))) void more_testing(char* buf, int len)
 	in8_2 = _mm_lddqu_si128((__m128i_u*)&buf[i + 16]);
     }
 }
-]], [[if (test_ssse3(42) != 42 || test_sse2(42) != 42 || test_avx2(42) != 42) exit(1);]])],[CXX_OK=yes],[CXX_OK=no])
+]], [[if (test_ssse3(42) != 42 || test_sse2(42) != 42 || test_avx2(42) != 42) exit(1);]])],[CXX_OK=yes],[CXX_OK=no],[CXX_OK=no])
 	AC_LANG(C)
 	if test x"$CXX_OK" = x"yes"; then
 	    # AC_MSG_RESULT() is called below.
From 7eb59a9152a2ace7bc7858e9915c671b3ab54344 Mon Sep 17 00:00:00 2001
From: Wayne Davison <wayne@opencoder.net>
Date: Tue, 22 Sep 2020 17:19:45 -0700
Subject: [PATCH] Change from $build_cpu to $host_cpu as edo1 suggested.

---
 configure.ac | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index 109546a6..e8c06f42 100644
--- a/configure.ac
+++ b/configure.ac
@@ -211,7 +211,7 @@ CXXFLAGS=`echo "$CXXFLAGS" | sed 's/-g //'`
 
 if test x"$enable_simd" != x"no"; then
     # For x86-64 SIMD, g++ >=5 or clang++ >=7 is required
-    if test x"$build_cpu" = x"x86_64"; then
+    if test x"$host_cpu" = x"x86_64"; then
 	AC_LANG(C++)
 	AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
 #include <immintrin.h>
@@ -283,8 +283,8 @@ AC_ARG_ENABLE(asm,
     AS_HELP_STRING([--disable-asm],[disable ASM optimizations]))
 
 if test x"$enable_asm" != x"no"; then
-    if test x"$build_cpu" = x"x86_64"; then
-	ASM="$build_cpu"
+    if test x"$host_cpu" = x"x86_64"; then
+	ASM="$host_cpu"
     elif test x"$enable_asm" = x"yes"; then
         AC_MSG_RESULT(unavailable)
         AC_MSG_ERROR(The ASM optimizations are currently x86_64 only.
From b7fab6f285ff0ff3816b109a8c3131b6ded0b484 Mon Sep 17 00:00:00 2001
From: edo <edo.rus@gmail.com>
Date: Wed, 7 Oct 2020 08:33:57 +0300
Subject: [PATCH] Allow cross-compilation with SIMD (x86_84) (#104)

Replace runtime SIMD check with a compile-only test in case of
cross-compilation.

You can still use '--enable-simd=no' to build x86_64 code without
SIMD instructions.
---
 configure.ac | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/configure.ac b/configure.ac
index 3fd7e5d5..e469981b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -208,12 +208,7 @@ AC_ARG_ENABLE(simd,
 
 # Clag is crashing with -g -O2, so we'll get rid of -g for now.
 CXXFLAGS=`echo "$CXXFLAGS" | sed 's/-g //'`
-
-if test x"$enable_simd" != x"no"; then
-    # For x86-64 SIMD, g++ >=5 or clang++ >=7 is required
-    if test x"$host_cpu" = x"x86_64"; then
-	AC_LANG(C++)
-	AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
+m4_define(SIMD_X86_64_TEST, [[#include <stdio.h>
 #include <immintrin.h>
 __attribute__ ((target("default"))) int test_ssse3(int x) { return x; }
 __attribute__ ((target("default"))) int test_sse2(int x) { return x; }
@@ -233,7 +228,18 @@ __attribute__ ((target("ssse3"))) void more_testing(char* buf, int len)
 	in8_2 = _mm_lddqu_si128((__m128i_u*)&buf[i + 16]);
     }
 }
-]], [[if (test_ssse3(42) != 42 || test_sse2(42) != 42 || test_avx2(42) != 42) exit(1);]])],[CXX_OK=yes],[CXX_OK=no],[CXX_OK=no])
+]])
+
+if test x"$enable_simd" != x"no"; then
+    # For x86-64 SIMD, g++ >=5 or clang++ >=7 is required
+    if test x"$host_cpu" = x"x86_64"; then
+	AC_LANG(C++)
+	if test x"$host_cpu" = x"$build_cpu"; then
+	    AC_RUN_IFELSE([AC_LANG_PROGRAM([SIMD_X86_64_TEST],[[if (test_ssse3(42) != 42 || test_sse2(42) != 42 || test_avx2(42) != 42) exit(1);]])],
+		[CXX_OK=yes],[CXX_OK=no])
+	else
+	    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([SIMD_X86_64_TEST])],[CXX_OK=yes],[CXX_OK=no])
+	fi
 	AC_LANG(C)
 	if test x"$CXX_OK" = x"yes"; then
 	    # AC_MSG_RESULT() is called below.
From 7d830ff52ff7b01f528f39aa27b1ab36ea8c1356 Mon Sep 17 00:00:00 2001
From: Andrew Aladjev <aladjev.andrew@gmail.com>
Date: Sun, 7 Nov 2021 22:45:49 +0300
Subject: [PATCH] improved cross compilation detection (#252)

---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index fbdd17d8..9e7338cf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -264,7 +264,7 @@ if test x"$enable_simd" != x"no"; then
     # For x86-64 SIMD, g++ >=5 or clang++ >=7 is required
     if test x"$host_cpu" = x"x86_64" || test x"$host_cpu" = x"amd64"; then
 	AC_LANG(C++)
-	if test x"$host_cpu" = x"$build_cpu"; then
+	if test x"$host" = x"$build"; then
 	    AC_RUN_IFELSE([AC_LANG_PROGRAM([SIMD_X86_64_TEST],[[if (test_ssse3(42) != 42 || test_sse2(42) != 42 || test_avx2(42) != 42) exit(1);]])],
 		[CXX_OK=yes],[CXX_OK=no])
 	else