Try to make sure struct _mcontext is 16-byte aligned

On x86_64, RtlCaptureContext() uses fxsave to save FPU/MMX/SSE state.

fxsave requires that the destination address is 16-byte aligned, or it will
fault.

CONTEXT is already annotated __attribute__ ((aligned (16))), do the same with
struct _mcontext.

Rearrange ucontext_t so that it's struct _mcontext element is also correctly
aligned.

	* include/cygwin/signal.h (struct __mcontext): 16-byte align.
	* include/sys/ucontext.h (ucontext_t): Ditto.

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
This commit is contained in:
Jon TURNEY 2015-04-02 18:05:32 +01:00
parent 94bb7da6b4
commit cbb9849fa7
3 changed files with 8 additions and 3 deletions

View File

@ -1,3 +1,8 @@
2015-04-02 Jon TURNEY <jon.turney@dronecode.org.uk>
* include/cygwin/signal.h (struct __mcontext): 16-byte align.
* include/sys/ucontext.h (ucontext_t): Ditto.
2015-04-02 Corinna Vinschen <corinna@vinschen.de> 2015-04-02 Corinna Vinschen <corinna@vinschen.de>
* sec_acl.cc (CYG_ACE_ISBITS_TO_WIN): Fix typo. * sec_acl.cc (CYG_ACE_ISBITS_TO_WIN): Fix typo.

View File

@ -49,7 +49,7 @@ struct _fpstate
__uint32_t padding[24]; __uint32_t padding[24];
}; };
struct __mcontext struct __attribute__ ((aligned (16))) __mcontext
{ {
__uint64_t p1home; __uint64_t p1home;
__uint64_t p2home; __uint64_t p2home;

View File

@ -15,11 +15,11 @@ details. */
typedef struct __mcontext mcontext_t; typedef struct __mcontext mcontext_t;
typedef struct __ucontext { typedef __attribute__ ((aligned (16))) struct __ucontext {
mcontext_t uc_mcontext;
struct __ucontext *uc_link; struct __ucontext *uc_link;
sigset_t uc_sigmask; sigset_t uc_sigmask;
stack_t uc_stack; stack_t uc_stack;
mcontext_t uc_mcontext;
unsigned long int uc_flags; unsigned long int uc_flags;
} ucontext_t; } ucontext_t;