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[PATCH] don't count return value space twice on x86
- From: Dan Witte <dwitte at mozilla dot com>
- To: libffi-discuss <libffi-discuss at sourceware dot org>
- Cc: Anthony Green <green at redhat dot com>
- Date: Wed, 4 Aug 2010 17:13:29 -0700 (PDT)
- Subject: [PATCH] don't count return value space twice on x86
Anthony,
There's a bug in stdcall x86 WIN32 closure code where stack space for the return value is counted twice -- which leads to overpopping and a spectacular crash. This adds an X86_ANY define for all x86 plats, which simplifies logic and means that stack computation is done consistently in the x86 prep_cif_machdep, rather than double-counted by prep_cif.
Look OK?
Cheers,
Dan.
diff --git a/ChangeLog b/ChangeLog
index 7ba744c..d5c1363 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2010-08-04 Dan Witte <dwitte@mozilla.com>
+
+ * src/x86/ffitarget.h: Add X86_ANY define for all x86/x86_64
+ platforms.
+ * src/x86/ffi.c: Remove redundant ifdef checks.
+ * src/prep_cif.c: Push stack space computation into src/x86/ffi.c
+ for X86_ANY so return value space doesn't get added twice.
+
2010-08-03 Neil Rashbrooke <neil@httl.net>
* msvcc.sh: Don't pass -safeseh to ml64 because behavior is buggy.
diff --git a/src/prep_cif.c b/src/prep_cif.c
index 5d749ef..761abdc 100644
--- a/src/prep_cif.c
+++ b/src/prep_cif.c
@@ -110,7 +110,7 @@ ffi_status ffi_prep_cif(ffi_cif *cif, ffi_abi abi, unsigned int nargs,
FFI_ASSERT_VALID_TYPE(cif->rtype);
/* x86, x86-64 and s390 stack space allocation is handled in prep_machdep. */
-#if !defined M68K && !defined __i386__ && !defined __x86_64__ && !defined S390 && !defined PA
+#if !defined M68K && !defined X86_ANY && !defined S390 && !defined PA
/* Make space for the return structure pointer */
if (cif->rtype->type == FFI_TYPE_STRUCT
#ifdef SPARC
@@ -131,7 +131,7 @@ ffi_status ffi_prep_cif(ffi_cif *cif, ffi_abi abi, unsigned int nargs,
check after the initialization. */
FFI_ASSERT_VALID_TYPE(*ptr);
-#if !defined __i386__ && !defined __x86_64__ && !defined S390 && !defined PA
+#if !defined X86_ANY && !defined S390 && !defined PA
#ifdef SPARC
if (((*ptr)->type == FFI_TYPE_STRUCT
&& ((*ptr)->size > 16 || cif->abi != FFI_V9))
diff --git a/src/x86/ffi.c b/src/x86/ffi.c
index 69a4dcd..bc14ce5 100644
--- a/src/x86/ffi.c
+++ b/src/x86/ffi.c
@@ -155,12 +155,10 @@ ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
switch (cif->rtype->type)
{
case FFI_TYPE_VOID:
-#if defined(X86) || defined (X86_WIN32) || defined(X86_FREEBSD) || defined(X86_DARWIN) || defined(X86_WIN64)
case FFI_TYPE_UINT8:
case FFI_TYPE_UINT16:
case FFI_TYPE_SINT8:
case FFI_TYPE_SINT16:
-#endif
#ifdef X86_WIN64
case FFI_TYPE_UINT32:
case FFI_TYPE_SINT32:
diff --git a/src/x86/ffitarget.h b/src/x86/ffitarget.h
index 2738875..542e6d4 100644
--- a/src/x86/ffitarget.h
+++ b/src/x86/ffitarget.h
@@ -31,6 +31,9 @@
/* ---- System specific configurations ----------------------------------- */
+/* For code common to all platforms on x86 and x86_64. */
+#define X86_ANY
+
#if defined (X86_64) && defined (__i386__)
#undef X86_64
#define X86
@@ -67,16 +70,14 @@ typedef enum ffi_abi {
FFI_LAST_ABI,
/* TODO: Add fastcall support for the sake of completeness */
FFI_DEFAULT_ABI = FFI_SYSV
-#endif
-#ifdef X86_WIN64
+#elif defined(X86_WIN64)
FFI_WIN64,
FFI_LAST_ABI,
FFI_DEFAULT_ABI = FFI_WIN64
-#else
+#else
/* ---- Intel x86 and AMD x86-64 - */
-#if !defined(X86_WIN32) && (defined(__i386__) || defined(__x86_64__) || defined(__i386) || defined(__amd64))
FFI_SYSV,
FFI_UNIX64, /* Unix variants all use the same ABI for x86-64 */
FFI_LAST_ABI,
@@ -86,7 +87,6 @@ typedef enum ffi_abi {
FFI_DEFAULT_ABI = FFI_UNIX64
#endif
#endif
-#endif /* X86_WIN64 */
} ffi_abi;
#endif