From d1f36ad0a881c450d756f56cd22a5b31e203f6ec Mon Sep 17 00:00:00 2001
From: =?utf8?q?Johannes=20Schl=C3=BCter?= <johannes@php.net>
Date: Tue, 9 Feb 2010 21:58:13 +0000
Subject: [PATCH] Detect if we can rely on compiler-specific alignment features
 else use custom workarounds. Fixes #50753

---
 ext/standard/config.m4      | 35 +++++++++++++++++++++++++++++++++++
 ext/standard/crypt_sha256.c | 15 +++++++++++----
 ext/standard/crypt_sha512.c | 15 +++++++++++----
 3 files changed, 57 insertions(+), 8 deletions(-)

diff --git a/ext/standard/config.m4 b/ext/standard/config.m4
index a25f47a2b6..bc7c7a369e 100644
--- a/ext/standard/config.m4
+++ b/ext/standard/config.m4
@@ -236,6 +236,41 @@ dnl
 dnl If one of them is missing, use our own implementation, portable code is then possible
 dnl
 if test "$ac_cv_crypt_blowfish" = "no" || test "$ac_cv_crypt_des" = "no" || test "$ac_cv_crypt_ext_des" = "no" || test "x$php_crypt_r" = "x0"; then
+
+  dnl
+  dnl Check for __alignof__ support in the compiler
+  dnl
+  AC_CACHE_CHECK(whether the compiler supports __alignof__,ac_cv_alignof_exists,[
+  AC_TRY_COMPILE([
+int main() {
+	int align = __alignof__(int);
+	return 0;
+}
+  ],[
+    ac_cv_alignof_exists=yes
+  ],[
+    ac_cv_alignof_exists=no
+  ])])
+  if test "$ac_cv_alignof_exists" = "yes"; then
+    AC_DEFINE([HAVE_ALIGNOF], 1, [whether the compiler supports __alignof__])
+  fi
+
+  dnl 
+  dnl Check for __attribute__ ((__aligned__)) support in the compiler
+  dnl
+  AC_CACHE_CHECK(whether the compiler supports aligned attribute,ac_cv_attribute_aligned,[
+  AC_TRY_COMPILE([
+    unsigned char test[32] __attribute__ ((__aligned__ (__alignof__ (int))));
+  ],[
+    ac_cv_attribute_aligned=yes
+  ],[
+    ac_cv_attribute_aligned=no
+  ])])
+  if test "$ac_cv_attribute_aligned" = "yes"; then
+    AC_DEFINE([HAVE_ATTRIBUTE_ALIGNED], 1, [wheter the compiler supports __attribute__ ((__aligned__))])
+  fi
+    
+
   AC_DEFINE_UNQUOTED(PHP_USE_PHP_CRYPT_R, 1, [Whether PHP has to use its own crypt_r for blowfish, des, ext des and md5])
   AC_DEFINE_UNQUOTED(PHP_STD_DES_CRYPT, 1, [Whether the system supports standard DES salt])
   AC_DEFINE_UNQUOTED(PHP_BLOWFISH_CRYPT, 1, [Whether the system supports BlowFish salt])
diff --git a/ext/standard/crypt_sha256.c b/ext/standard/crypt_sha256.c
index c33855f5f5..67429e467a 100644
--- a/ext/standard/crypt_sha256.c
+++ b/ext/standard/crypt_sha256.c
@@ -18,6 +18,15 @@
 # elif HAVE_STDINT_H
 #  include <stdint.h>
 # endif
+# ifndef HAVE_ALIGNOF
+#  include <stddef.h>
+#  define __alignof__(type) offsetof (struct { char c; type member;}, member)
+# endif
+# if HAVE_ATTRIBUTE_ALIGNED
+#  define ALIGNED(size) __attribute__ ((__aligned__ (size)))
+# else
+#  define ALIGNED(size)
+# endif
 #endif
 
 #include <stdio.h>
@@ -335,10 +344,8 @@ char * php_sha256_crypt_r(const char *key, const char *salt, char *buffer, int b
 	__declspec(align(32)) unsigned char alt_result[32];
 	__declspec(align(32)) unsigned char temp_result[32];
 #else
-	unsigned char alt_result[32]
-	__attribute__ ((__aligned__ (__alignof__ (uint32_t))));
-	unsigned char temp_result[32]
-	__attribute__ ((__aligned__ (__alignof__ (uint32_t))));
+	unsigned char alt_result[32] ALIGNED(__alignof__ (uint32_t));
+	unsigned char temp_result[32] ALIGNED(__alignof__ (uint32_t));
 #endif
 
 	struct sha256_ctx ctx;
diff --git a/ext/standard/crypt_sha512.c b/ext/standard/crypt_sha512.c
index f32e4a0f8a..1d76b3bbf4 100644
--- a/ext/standard/crypt_sha512.c
+++ b/ext/standard/crypt_sha512.c
@@ -17,6 +17,15 @@
 # elif HAVE_STDINT_H
 #  include <stdint.h>
 # endif
+# ifndef HAVE_ALIGNOF
+#  include <stddef.h>
+#  define __alignof__(type) offsetof (struct { char c; type member;}, member)
+# endif
+# if HAVE_ATTRIBUTE_ALIGNED
+#  define ALIGNED(size) __attribute__ ((__aligned__ (size)))
+# else
+#  define ALIGNED(size)
+# endif
 #endif
 
 #include <stdio.h>
@@ -363,10 +372,8 @@ php_sha512_crypt_r(const char *key, const char *salt, char *buffer, int buflen)
 	__declspec(align(64)) unsigned char alt_result[64];
 	__declspec(align(64)) unsigned char temp_result[64];
 #else
-	unsigned char alt_result[64]
-		__attribute__ ((__aligned__ (__alignof__ (uint64_t))));
-	unsigned char temp_result[64]
-		__attribute__ ((__aligned__ (__alignof__ (uint64_t))));
+	unsigned char alt_result[64] ALIGNED(__alignof__ (uint64_t));
+	unsigned char temp_result[64] ALIGNED(__alignof__ (uint64_t));
 #endif
 	struct sha512_ctx ctx;
 	struct sha512_ctx alt_ctx;
-- 
2.40.0