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Remove incorrect __restrict qualifier on several pointers

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The typical case was:
static __inline int
convert_ccl(FILE *fp, char * __restrict p, [...])
{
        [...]

        if (p == SUPPRESS_PTR) {
		[...]
	} else {
		[...]
	}

	[...]
}

This qualifier says that the pointer is the only one at that time
pointing to the resource.

Here, clang considers that "p" will never match "SUPPRESS_PTR" and
optimize the if{} block out. This leads to segfaults in programs calling
vfscanf(3) and vfwscanf(3) with just the format string (no arguments
following it).

The following softwares were reported to abort with segmentation fault
and this patch fixes it:
    o  cmake
    o  smartd
    o  devel/ORBit2

dim@ opened an LLVM PR to discuss this clang optimization:
    http://llvm.org/bugs/show_bug.cgi?id=12656

Tested by:	bsam@
This commit is contained in:
Jean-Sébastien Pédron 2012-04-30 11:28:17 +00:00
parent 7bd5e9b143
commit 671c033623
2 changed files with 9 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
lib/libc/stdio/vfscanf.c
View File

@ -125,7 +125,7 @@ static const mbstate_t initial_mbs;
*/
static __inline int
convert_char(FILE *fp, char * __restrict p, int width)
convert_char(FILE *fp, char * p, int width)
{
int n;
@ -151,7 +151,7 @@ convert_char(FILE *fp, char * __restrict p, int width)
return (sum);
} else {
size_t r = __fread(p, 1, width, fp);
if (r == 0)
return (-1);
return (r);
@ -179,7 +179,7 @@ convert_wchar(FILE *fp, wchar_t *wcp, int width, locale_t locale)
}
static __inline int
convert_ccl(FILE *fp, char * __restrict p, int width, const char *ccltab)
convert_ccl(FILE *fp, char * p, int width, const char *ccltab)
{
char *p0;
int n;
@ -249,7 +249,7 @@ convert_wccl(FILE *fp, wchar_t *wcp, int width, const char *ccltab,
}
static __inline int
convert_string(FILE *fp, char * __restrict p, int width)
convert_string(FILE *fp, char * p, int width)
{
char *p0;
int n;
@ -387,7 +387,7 @@ parseint(FILE *fp, char * __restrict buf, int width, int base, int flags)
goto ok;
}
break;
/*
* x ok iff flag still set & 2nd char (or 3rd char if
* we have a sign).

8
lib/libc/stdio/vfwscanf.c
View File

@ -138,7 +138,7 @@ static const mbstate_t initial_mbs;
*/
static __inline int
convert_char(FILE *fp, char * __restrict mbp, int width, locale_t locale)
convert_char(FILE *fp, char * mbp, int width, locale_t locale)
{
mbstate_t mbs;
size_t nconv;
@ -179,7 +179,7 @@ convert_wchar(FILE *fp, wchar_t *wcp, int width, locale_t locale)
}
static __inline int
convert_ccl(FILE *fp, char * __restrict mbp, int width, const struct ccl *ccl,
convert_ccl(FILE *fp, char * mbp, int width, const struct ccl *ccl,
locale_t locale)
{
mbstate_t mbs;
@ -237,7 +237,7 @@ convert_wccl(FILE *fp, wchar_t *wcp, int width, const struct ccl *ccl,
}
static __inline int
convert_string(FILE *fp, char * __restrict mbp, int width, locale_t locale)
convert_string(FILE *fp, char * mbp, int width, locale_t locale)
{
mbstate_t mbs;
size_t nconv;
@ -372,7 +372,7 @@ parseint(FILE *fp, wchar_t *buf, int width, int base, int flags,
goto ok;
}
break;
/*
* x ok iff flag still set & 2nd char (or 3rd char if
* we have a sign).