Fixes bug 1296 - SDL_SetVideoMode crashes because of unaligned MOVAPS instruction

t.grundner@goto3d.de 2011-09-01 03:59:17 PDT I figured out what is going on. GCC 4.5.2 assumes the stack is 16 byte aligned by default. Therefore there are no AND alignment corrections necessary if we wish to align a stack variable to a 16 byte boundary. That is bad if your OS ABI is not 16 byte aligned. Windows 32 bit stacks are 4 byte aligned. This results in the above mentioned SIGSEGV. This is also no problem if I compile both SDL.dll and my app with MingW because MinGW/GCC inserts a andl $-16, %esp instruction right in the beginning of the main function. So at least the stack of the thread calling the main function is 16 byte aligned. But as soon as I start to use the SDL.dll from an application not compiled by MinGW there is no ANDL safing my app. However there is a GCC option that can change the default stack alignment: -mpreferred-stack-boundary=num Setting num=2 assumes a the stack is aligned to a 4 byte boundary. This results in GCC inserting the necessary andl $-16, %esp into SDL_FillRect. Rebuilding SDL with ./configure "CFLAGS=-mpreferred-stack-boundary=2 -g -O3" solved the problem. IMHO this should also be a problem on Solaris. The following links contain further information: http://gcc.gnu.org/onlinedocs/gcc-4.5.2/gcc/i386-and-x86_002d64-Options.html#i386-and-x86_002d64-Options http://www.agner.org/optimize/calling_conventions.pdf

Fixes bug 1296 - SDL_SetVideoMode crashes because of unaligned MOVAPS instruction
t.grundner@goto3d.de 2011-09-01 03:59:17 PDT I figured out what is going on. GCC 4.5.2 assumes the stack is 16 byte aligned by default. Therefore there are no AND alignment corrections necessary if we wish to align a stack variable to a 16 byte boundary. That is bad if your OS ABI is not 16 byte aligned. Windows 32 bit stacks are 4 byte aligned. This results in the above mentioned SIGSEGV. This is also no problem if I compile both SDL.dll and my app with MingW because MinGW/GCC inserts a andl $-16, %esp instruction right in the beginning of the main function. So at least the stack of the thread calling the main function is 16 byte aligned. But as soon as I start to use the SDL.dll from an application not compiled by MinGW there is no ANDL safing my app. However there is a GCC option that can change the default stack alignment: -mpreferred-stack-boundary=num Setting num=2 assumes a the stack is aligned to a 4 byte boundary. This results in GCC inserting the necessary andl $-16, %esp into SDL_FillRect. Rebuilding SDL with ./configure "CFLAGS=-mpreferred-stack-boundary=2 -g -O3" solved the problem. IMHO this should also be a problem on Solaris. The following links contain further information: http://gcc.gnu.org/onlinedocs/gcc-4.5.2/gcc/i386-and-x86_002d64-Options.html#i386-and-x86_002d64-Options http://www.agner.org/optimize/calling_conventions.pdf
f5c28b24 · Sam Lantinga · ad85c9da · f5c28b24 · f5c28b24 · f5c28b24
Commit f5c28b24 authored Dec 29, 2011 by Sam Lantinga
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Showing with 363 additions and 18 deletions

configure configure +67 -0

configure.in configure.in +27 -0

SDL_config.h include/SDL_config.h +269 -18

No files found.
--- a/configure
+++ b/configure
@@ -20593,6 +20593,70 @@ echo "${ECHO_T}$have_gcc_fvisibility" >&6; }
    fi
 }

+CheckStackBoundary()
+{
+    { echo "$as_me:$LINENO: checking for GCC -mpreferred-stack-boundary option" >&5
+echo $ECHO_N "checking for GCC -mpreferred-stack-boundary option... $ECHO_C" >&6; }
+    have_gcc_preferred_stack_boundary=no
+
+    save_CFLAGS="$CFLAGS"
+    CFLAGS="$save_CFLAGS -mpreferred-stack-boundary=2"
+    cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+    int x = 0;
+
+int
+main ()
+{
+
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+
+    have_gcc_preferred_stack_boundary=yes
+
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+    { echo "$as_me:$LINENO: result: $have_gcc_preferred_stack_boundary" >&5
+echo "${ECHO_T}$have_gcc_preferred_stack_boundary" >&6; }
+    CFLAGS="$save_CFLAGS"
+
+    if test x$have_gcc_preferred_stack_boundary = xyes; then
+        EXTRA_CFLAGS="$EXTRA_CFLAGS -mpreferred-stack-boundary=2"
+    fi
+}
+
+
 CheckWarnAll()
 {
    { echo "$as_me:$LINENO: checking for GCC -Wall option" >&5
@@ -24695,6 +24759,9 @@ fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
    { echo "$as_me:$LINENO: result: $have_wince" >&5
 echo "${ECHO_T}$have_wince" >&6; }
+
+    # This fixes Windows stack alignment with newer GCC
+    CheckStackBoundary
 }

 CheckDIRECTX()

--- a/configure.in
+++ b/configure.in
@@ -939,6 +939,30 @@ CheckVisibilityHidden()
    fi
 }

+dnl See if GCC's -mpreferred-stack-boundary is supported.
+dnl  Reference: http://bugzilla.libsdl.org/show_bug.cgi?id=1296
+CheckStackBoundary()
+{
+    AC_MSG_CHECKING(for GCC -mpreferred-stack-boundary option)
+    have_gcc_preferred_stack_boundary=no
+
+    save_CFLAGS="$CFLAGS"
+    CFLAGS="$save_CFLAGS -mpreferred-stack-boundary=2"
+    AC_TRY_COMPILE([
+    int x = 0;
+    ],[
+    ],[
+    have_gcc_preferred_stack_boundary=yes
+    ])
+    AC_MSG_RESULT($have_gcc_preferred_stack_boundary)
+    CFLAGS="$save_CFLAGS"
+
+    if test x$have_gcc_preferred_stack_boundary = xyes; then
+        EXTRA_CFLAGS="$EXTRA_CFLAGS -mpreferred-stack-boundary=2"
+    fi
+}
+
+
 dnl See if GCC's -Wall is supported.
 CheckWarnAll()
 {
@@ -1757,6 +1781,9 @@ CheckWINDOWS()
    have_wince=yes
    ])
    AC_MSG_RESULT($have_wince)
+
+    # This fixes Windows stack alignment with newer GCC
+    CheckStackBoundary
 }

 dnl Find the DirectX includes and libraries

--- a/include/SDL_config.h
+++ b/include/SDL_config.h
+/* include/SDL_config.h.  Generated from SDL_config.h.in by configure.  */
 /*
  Simple DirectMedia Layer
  Copyright (C) 1997-2011 Sam Lantinga <slouken@libsdl.org>
@@ -22,27 +23,277 @@
 #ifndef _SDL_config_h
 #define _SDL_config_h

-#include "SDL_platform.h"
-
 /**
- *  \file SDL_config.h
+ *  \file SDL_config.h.in
 *
- *  SDL_config.h for any platform that doesn't build using the configure system.
+ *  This is a set of defines to configure the SDL features
 */
- 
-/* Add any platform that doesn't build using the configure system. */
-#if defined(__WIN32__)
-#include "SDL_config_windows.h"
-#elif defined(__MACOSX__)
-#include "SDL_config_macosx.h"
-#elif defined(__IPHONEOS__) 
-#include "SDL_config_iphoneos.h"
-#elif defined(__ANDROID__)
-#include "SDL_config_android.h"
-#elif defined(__NINTENDODS__)
-#include "SDL_config_nintendods.h"
+
+/* General platform specific identifiers */
+#include "SDL_platform.h"
+
+/* Make sure that this isn't included by Visual C++ */
+#ifdef _MSC_VER
+#error You should run hg revert SDL_config.h 
+#endif
+
+/* C language features */
+/* #undef const */
+/* #undef inline */
+/* #undef volatile */
+
+/* C datatypes */
+#define SIZEOF_VOIDP 8
+#define HAVE_GCC_ATOMICS 1
+/* #undef HAVE_GCC_SYNC_LOCK_TEST_AND_SET */
+/* #undef HAVE_PTHREAD_SPINLOCK */
+
+/* Comment this if you want to build without any C library requirements */
+#define HAVE_LIBC 1
+#if HAVE_LIBC
+
+/* Useful headers */
+#define HAVE_ALLOCA_H 1
+#define HAVE_SYS_TYPES_H 1
+#define HAVE_STDIO_H 1
+#define STDC_HEADERS 1
+#define HAVE_STDLIB_H 1
+#define HAVE_STDARG_H 1
+/* #undef HAVE_MALLOC_H */
+#define HAVE_MEMORY_H 1
+#define HAVE_STRING_H 1
+#define HAVE_STRINGS_H 1
+#define HAVE_INTTYPES_H 1
+#define HAVE_STDINT_H 1
+#define HAVE_CTYPE_H 1
+#define HAVE_MATH_H 1
+#define HAVE_ICONV_H 1
+#define HAVE_SIGNAL_H 1
+/* #undef HAVE_ALTIVEC_H */
+/* #undef HAVE_PTHREAD_NP_H */
+
+/* C library functions */
+#define HAVE_MALLOC 1
+#define HAVE_CALLOC 1
+#define HAVE_REALLOC 1
+#define HAVE_FREE 1
+#define HAVE_ALLOCA 1
+#ifndef __WIN32__ /* Don't use C runtime versions of these on Windows */
+#define HAVE_GETENV 1
+#define HAVE_SETENV 1
+#define HAVE_PUTENV 1
+#define HAVE_UNSETENV 1
+#endif
+#define HAVE_QSORT 1
+#define HAVE_ABS 1
+#define HAVE_BCOPY 1
+#define HAVE_MEMSET 1
+#define HAVE_MEMCPY 1
+#define HAVE_MEMMOVE 1
+#define HAVE_MEMCMP 1
+#define HAVE_STRLEN 1
+#define HAVE_STRLCPY 1
+#define HAVE_STRLCAT 1
+#define HAVE_STRDUP 1
+/* #undef HAVE__STRREV */
+/* #undef HAVE__STRUPR */
+/* #undef HAVE__STRLWR */
+/* #undef HAVE_INDEX */
+/* #undef HAVE_RINDEX */
+#define HAVE_STRCHR 1
+#define HAVE_STRRCHR 1
+#define HAVE_STRSTR 1
+/* #undef HAVE_ITOA */
+/* #undef HAVE__LTOA */
+/* #undef HAVE__UITOA */
+/* #undef HAVE__ULTOA */
+#define HAVE_STRTOL 1
+#define HAVE_STRTOUL 1
+/* #undef HAVE__I64TOA */
+/* #undef HAVE__UI64TOA */
+#define HAVE_STRTOLL 1
+#define HAVE_STRTOULL 1
+#define HAVE_STRTOD 1
+#define HAVE_ATOI 1
+#define HAVE_ATOF 1
+#define HAVE_STRCMP 1
+#define HAVE_STRNCMP 1
+/* #undef HAVE__STRICMP */
+#define HAVE_STRCASECMP 1
+/* #undef HAVE__STRNICMP */
+#define HAVE_STRNCASECMP 1
+#define HAVE_SSCANF 1
+#define HAVE_SNPRINTF 1
+#define HAVE_VSNPRINTF 1
+#define HAVE_M_PI 
+#define HAVE_ATAN 1
+#define HAVE_ATAN2 1
+#define HAVE_CEIL 1
+#define HAVE_COPYSIGN 1
+#define HAVE_COS 1
+#define HAVE_COSF 1
+#define HAVE_FABS 1
+#define HAVE_FLOOR 1
+#define HAVE_LOG 1
+#define HAVE_POW 1
+#define HAVE_SCALBN 1
+#define HAVE_SIN 1
+#define HAVE_SINF 1
+#define HAVE_SQRT 1
+#define HAVE_SIGACTION 1
+#define HAVE_SA_SIGACTION 1
+#define HAVE_SETJMP 1
+#define HAVE_NANOSLEEP 1
+#define HAVE_SYSCONF 1
+#define HAVE_SYSCTLBYNAME 1
+/* #undef HAVE_CLOCK_GETTIME */
+/* #undef HAVE_GETPAGESIZE */
+#define HAVE_MPROTECT 1
+#define HAVE_ICONV 1
+#define HAVE_PTHREAD_SETNAME_NP 1
+/* #undef HAVE_PTHREAD_SET_NAME_NP */
+
 #else
-#include "SDL_config_minimal.h"
-#endif /* platform config */
+/* We may need some replacement for stdarg.h here */
+#include <stdarg.h>
+#endif /* HAVE_LIBC */
+
+/* SDL internal assertion support */
+/* #undef SDL_DEFAULT_ASSERT_LEVEL */
+
+/* Allow disabling of core subsystems */
+/* #undef SDL_ATOMIC_DISABLED */
+/* #undef SDL_AUDIO_DISABLED */
+/* #undef SDL_CPUINFO_DISABLED */
+/* #undef SDL_EVENTS_DISABLED */
+/* #undef SDL_FILE_DISABLED */
+/* #undef SDL_JOYSTICK_DISABLED */
+/* #undef SDL_HAPTIC_DISABLED */
+/* #undef SDL_LOADSO_DISABLED */
+/* #undef SDL_RENDER_DISABLED */
+/* #undef SDL_THREADS_DISABLED */
+/* #undef SDL_TIMERS_DISABLED */
+/* #undef SDL_VIDEO_DISABLED */
+/* #undef SDL_POWER_DISABLED */
+
+/* Enable various audio drivers */
+/* #undef SDL_AUDIO_DRIVER_ALSA */
+/* #undef SDL_AUDIO_DRIVER_ALSA_DYNAMIC */
+/* #undef SDL_AUDIO_DRIVER_ARTS */
+/* #undef SDL_AUDIO_DRIVER_ARTS_DYNAMIC */
+/* #undef SDL_AUDIO_DRIVER_PULSEAUDIO */
+/* #undef SDL_AUDIO_DRIVER_PULSEAUDIO_DYNAMIC */
+/* #undef SDL_AUDIO_DRIVER_BEOSAUDIO */
+/* #undef SDL_AUDIO_DRIVER_BSD */
+#define SDL_AUDIO_DRIVER_COREAUDIO 1
+#define SDL_AUDIO_DRIVER_DISK 1
+#define SDL_AUDIO_DRIVER_DUMMY 1
+/* #undef SDL_AUDIO_DRIVER_XAUDIO2 */
+/* #undef SDL_AUDIO_DRIVER_DSOUND */
+/* #undef SDL_AUDIO_DRIVER_ESD */
+/* #undef SDL_AUDIO_DRIVER_ESD_DYNAMIC */
+/* #undef SDL_AUDIO_DRIVER_NAS */
+/* #undef SDL_AUDIO_DRIVER_NAS_DYNAMIC */
+/* #undef SDL_AUDIO_DRIVER_NDS */
+/* #undef SDL_AUDIO_DRIVER_OSS */
+/* #undef SDL_AUDIO_DRIVER_OSS_SOUNDCARD_H */
+/* #undef SDL_AUDIO_DRIVER_PAUDIO */
+/* #undef SDL_AUDIO_DRIVER_QSA */
+/* #undef SDL_AUDIO_DRIVER_SUNAUDIO */
+/* #undef SDL_AUDIO_DRIVER_WINMM */
+/* #undef SDL_AUDIO_DRIVER_FUSIONSOUND */
+/* #undef SDL_AUDIO_DRIVER_FUSIONSOUND_DYNAMIC */
+
+/* Enable various input drivers */
+/* #undef SDL_INPUT_LINUXEV */
+/* #undef SDL_INPUT_TSLIB */
+/* #undef SDL_JOYSTICK_BEOS */
+/* #undef SDL_JOYSTICK_DINPUT */
+/* #undef SDL_JOYSTICK_DUMMY */
+#define SDL_JOYSTICK_IOKIT 1
+/* #undef SDL_JOYSTICK_LINUX */
+/* #undef SDL_JOYSTICK_NDS */
+/* #undef SDL_JOYSTICK_WINMM */
+/* #undef SDL_JOYSTICK_USBHID */
+/* #undef SDL_JOYSTICK_USBHID_MACHINE_JOYSTICK_H */
+/* #undef SDL_HAPTIC_DUMMY */
+/* #undef SDL_HAPTIC_LINUX */
+#define SDL_HAPTIC_IOKIT 1
+/* #undef SDL_HAPTIC_DINPUT */
+
+/* Enable various shared object loading systems */
+/* #undef SDL_LOADSO_BEOS */
+#define SDL_LOADSO_DLOPEN 1
+/* #undef SDL_LOADSO_DUMMY */
+/* #undef SDL_LOADSO_LDG */
+/* #undef SDL_LOADSO_WINDOWS */
+
+/* Enable various threading systems */
+/* #undef SDL_THREAD_BEOS */
+/* #undef SDL_THREAD_NDS */
+#define SDL_THREAD_PTHREAD 1
+#define SDL_THREAD_PTHREAD_RECURSIVE_MUTEX 1
+/* #undef SDL_THREAD_PTHREAD_RECURSIVE_MUTEX_NP */
+/* #undef SDL_THREAD_WINDOWS */
+
+/* Enable various timer systems */
+/* #undef SDL_TIMER_BEOS */
+/* #undef SDL_TIMER_DUMMY */
+/* #undef SDL_TIMER_NDS */
+#define SDL_TIMER_UNIX 1
+/* #undef SDL_TIMER_WINDOWS */
+/* #undef SDL_TIMER_WINCE */
+
+/* Enable various video drivers */
+/* #undef SDL_VIDEO_DRIVER_BWINDOW */
+#define SDL_VIDEO_DRIVER_COCOA 1
+/* #undef SDL_VIDEO_DRIVER_DIRECTFB */
+/* #undef SDL_VIDEO_DRIVER_DIRECTFB_DYNAMIC */
+#define SDL_VIDEO_DRIVER_DUMMY 1
+/* #undef SDL_VIDEO_DRIVER_NDS */
+/* #undef SDL_VIDEO_DRIVER_WINDOWS */
+#define SDL_VIDEO_DRIVER_X11 1
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC "/usr/X11R6/lib/libX11.6.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XEXT "/usr/X11R6/lib/libXext.6.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XCURSOR "/usr/X11R6/lib/libXcursor.1.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XINERAMA "/usr/X11R6/lib/libXinerama.1.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XINPUT "/usr/X11R6/lib/libXi.6.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XRANDR "/usr/X11R6/lib/libXrandr.2.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XSS "/usr/X11R6/lib/libXss.1.dylib"
+#define SDL_VIDEO_DRIVER_X11_DYNAMIC_XVIDMODE "/usr/X11R6/lib/libXxf86vm.1.dylib"
+#define SDL_VIDEO_DRIVER_X11_XCURSOR 1
+#define SDL_VIDEO_DRIVER_X11_XINERAMA 1
+#define SDL_VIDEO_DRIVER_X11_XINPUT 1
+#define SDL_VIDEO_DRIVER_X11_XRANDR 1
+#define SDL_VIDEO_DRIVER_X11_XSCRNSAVER 1
+#define SDL_VIDEO_DRIVER_X11_XSHAPE 1
+#define SDL_VIDEO_DRIVER_X11_XVIDMODE 1
+
+/* #undef SDL_VIDEO_RENDER_D3D */
+#define SDL_VIDEO_RENDER_OGL 1
+/* #undef SDL_VIDEO_RENDER_OGL_ES */
+/* #undef SDL_VIDEO_RENDER_DIRECTFB */
+
+/* Enable OpenGL support */
+#define SDL_VIDEO_OPENGL 1
+/* #undef SDL_VIDEO_OPENGL_ES */
+/* #undef SDL_VIDEO_OPENGL_BGL */
+#define SDL_VIDEO_OPENGL_CGL 1
+#define SDL_VIDEO_OPENGL_GLX 1
+/* #undef SDL_VIDEO_OPENGL_WGL */
+/* #undef SDL_VIDEO_OPENGL_OSMESA */
+/* #undef SDL_VIDEO_OPENGL_OSMESA_DYNAMIC */
+
+/* Enable system power support */
+/* #undef SDL_POWER_LINUX */
+/* #undef SDL_POWER_WINDOWS */
+#define SDL_POWER_MACOSX 1
+/* #undef SDL_POWER_BEOS */
+/* #undef SDL_POWER_NINTENDODS */
+/* #undef SDL_POWER_HARDWIRED */
+
+/* Enable assembly routines */
+#define SDL_ASSEMBLY_ROUTINES 1
+/* #undef SDL_ALTIVEC_BLITTERS */

 #endif /* _SDL_config_h */