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tile: use better variable naming in INLINE_SYSCALL

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At issue for INLINE_SYSCALL was that it used "err" and "val"
as variable names in a #define, so that if it was used in a context
where the "caller" was also using "err" or "val", and those
variables were passed in to INLINE_SYSCALL, we would end up
referencing the internal shadowed variables instead.

For example, "char val" in check_may_shrink_heap() in
sysdeps/unix/sysv/linux/malloc-sysdep.h was being shadowed by
the syscall return "val" in INLINE_SYSCALL, causing the "char val"
not to get updated at all, and may_shrink_heap ended up always false.

A similar fix was made to INTERNAL_VSYSCALL_CALL.
This commit is contained in:
Chris Metcalf 2015-05-26 20:29:56 -04:00
parent 4da82229f0
commit 1827059925
2 changed files with 21 additions and 14 deletions
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6
ChangeLog
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@ -1,3 +1,9 @@
2015-05-26 Chris Metcalf <cmetcalf@ezchip.com>
* sysdeps/unix/sysv/linux/tile/sysdep.h (INLINE_SYSCALL):
Avoid using variables in #defines that might cause shadowing.
(INTERNAL_VSYSCALL_CALL): Likewise.
2015-05-26 Roland McGrath <roland@hack.frob.com>
* sysdeps/nacl/lll_timedlock_wait.c: New file.

29
sysdeps/unix/sysv/linux/tile/sysdep.h
View File

@ -78,16 +78,17 @@
/* Define a macro which expands inline into the wrapper code for a system
call. */
# undef INLINE_SYSCALL
# define INLINE_SYSCALL(name, nr, args...) \
# define INLINE_SYSCALL(name, nr, args...) \
({ \
INTERNAL_SYSCALL_DECL (err); \
unsigned long val = INTERNAL_SYSCALL (name, err, nr, args); \
if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (val, err), 0)) \
{ \
__set_errno (INTERNAL_SYSCALL_ERRNO (val, err)); \
val = -1; \
} \
(long) val; })
INTERNAL_SYSCALL_DECL (_sc_err); \
unsigned long _sc_val = INTERNAL_SYSCALL (name, _sc_err, nr, args); \
if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_sc_val, _sc_err), 0)) \
{ \
__set_errno (INTERNAL_SYSCALL_ERRNO (_sc_val, _sc_err)); \
_sc_val = -1; \
} \
(long) _sc_val; \
})
#undef INTERNAL_SYSCALL
#define INTERNAL_SYSCALL(name, err, nr, args...) \
@ -203,11 +204,11 @@
"=R05" (_clobber_r5), "=R10" (_clobber_r10)
#define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...) \
({ \
struct syscall_return_value rv = funcptr (args); \
err = rv.error; \
rv.value; \
#define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...) \
({ \
struct syscall_return_value _sc_rv = funcptr (args); \
err = _sc_rv.error; \
_sc_rv.value; \
})
/* List of system calls which are supported as vsyscalls. */