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| author | Martin Jansa <Martin.Jansa@gmail.com> | 2018-10-02 15:38:43 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2018-10-02 15:40:57 +0000 |
| commit | 4a06ceea33ecc220bbfe264d8f1e74de2f04e90d (patch) | |
| tree | b5713f32622f034efc25c5266e0824e3f134c908 | |
| parent | a06fc4a53385709f80a866075f794646810b831e (diff) | |
| download | glibc-4a06ceea33ecc220bbfe264d8f1e74de2f04e90d.tar.gz glibc-4a06ceea33ecc220bbfe264d8f1e74de2f04e90d.tar.xz glibc-4a06ceea33ecc220bbfe264d8f1e74de2f04e90d.zip | |
sysdeps/ieee754/soft-fp: ignore maybe-uninitialized with -O [BZ #19444]
* with -O, -O1, -Os it fails with:
In file included from ../soft-fp/soft-fp.h:318,
from ../sysdeps/ieee754/soft-fp/s_fdiv.c:28:
../sysdeps/ieee754/soft-fp/s_fdiv.c: In function '__fdiv':
../soft-fp/op-2.h:98:25: error: 'R_f1' may be used uninitialized in this function [-Werror=maybe-uninitialized]
X##_f0 = (X##_f1 << (_FP_W_TYPE_SIZE - (N)) | X##_f0 >> (N) \
^~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:14: note: 'R_f1' was declared here
FP_DECL_D (R);
^
../soft-fp/op-2.h:37:36: note: in definition of macro '_FP_FRAC_DECL_2'
_FP_W_TYPE X##_f0 _FP_ZERO_INIT, X##_f1 _FP_ZERO_INIT
^
../soft-fp/double.h:95:24: note: in expansion of macro '_FP_DECL'
# define FP_DECL_D(X) _FP_DECL (2, X)
^~~~~~~~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:3: note: in expansion of macro 'FP_DECL_D'
FP_DECL_D (R);
^~~~~~~~~
../soft-fp/op-2.h:101:17: error: 'R_f0' may be used uninitialized in this function [-Werror=maybe-uninitialized]
: (X##_f0 << (_FP_W_TYPE_SIZE - (N))) != 0)); \
^~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:14: note: 'R_f0' was declared here
FP_DECL_D (R);
^
../soft-fp/op-2.h:37:14: note: in definition of macro '_FP_FRAC_DECL_2'
_FP_W_TYPE X##_f0 _FP_ZERO_INIT, X##_f1 _FP_ZERO_INIT
^
../soft-fp/double.h:95:24: note: in expansion of macro '_FP_DECL'
# define FP_DECL_D(X) _FP_DECL (2, X)
^~~~~~~~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:3: note: in expansion of macro 'FP_DECL_D'
FP_DECL_D (R);
^~~~~~~~~
Build tested with Yocto for ARM, AARCH64, X86, X86_64, PPC, MIPS, MIPS64
with -O, -O1, -Os.
For AARCH64 it needs one more fix in locale for -Os.
[BZ #19444]
* sysdeps/ieee754/soft-fp/s_fdiv.c: Include <libc-diag.h> and use
DIAG_PUSH_NEEDS_COMMENT, DIAG_IGNORE_NEEDS_COMMENT and
DIAG_POP_NEEDS_COMMENT to disable -Wmaybe-uninitialized.
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | sysdeps/ieee754/soft-fp/s_fdiv.c | 12 |
2 files changed, 19 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index 8128582eb7..12c7fcc4f8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2018-10-02 Martin Jansa <Martin.Jansa@gmail.com> + + [BZ #19444] + * sysdeps/ieee754/soft-fp/s_fdiv.c: Include <libc-diag.h> and use + DIAG_PUSH_NEEDS_COMMENT, DIAG_IGNORE_NEEDS_COMMENT and + DIAG_POP_NEEDS_COMMENT to disable -Wmaybe-uninitialized. + 2018-10-02 Adhemerval Zanella <adhemerval.zanella@linaro.org> * sysdeps/unix/sysv/linux/fd_to_filename.h: Add missing includes. diff --git a/sysdeps/ieee754/soft-fp/s_fdiv.c b/sysdeps/ieee754/soft-fp/s_fdiv.c index 341339f5ed..7a15cbeee6 100644 --- a/sysdeps/ieee754/soft-fp/s_fdiv.c +++ b/sysdeps/ieee754/soft-fp/s_fdiv.c @@ -25,6 +25,16 @@ #undef fdivl #include <math-narrow.h> +#include <libc-diag.h> + +/* R_f[01] are not set in cases where they are not used in packing, + but the compiler does not see that they are set in all cases where + they are used, resulting in warnings that they may be used + uninitialized. The location of the warning differs in different + versions of GCC, it may be where R is defined using a macro or it + may be where the macro is defined. This happens only with -O1. */ +DIAG_PUSH_NEEDS_COMMENT; +DIAG_IGNORE_NEEDS_COMMENT (8, "-Wmaybe-uninitialized"); #include <soft-fp.h> #include <single.h> #include <double.h> @@ -53,4 +63,6 @@ __fdiv (double x, double y) CHECK_NARROW_DIV (ret, x, y); return ret; } +DIAG_POP_NEEDS_COMMENT; + libm_alias_float_double (div) |