diff options
| author | Joseph Myers <joseph@codesourcery.com> | 2017-06-22 22:46:27 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2017-06-22 22:46:27 +0000 |
| commit | d08cdabdd096325a3296713c87672f213b05f5c6 (patch) | |
| tree | 8bc7b48f8a43c030f8f1b9e7bfa82cefb23c139e | |
| parent | 46d2e49c49165c09d8ebf555e56d74d063102342 (diff) | |
| download | glibc-d08cdabdd096325a3296713c87672f213b05f5c6.tar.gz | |
Correct min_of_type handling of _Float128.
The math_private.h macro min_of_type has broken _Float128 handling:
instead of passing its type argument to the key __EXPR_FLT128 macro,
it passes x, which is not a macro argument but whatever variable
called x happens to be visible in the calling function. If that
variable has the wrong type, the wrong one of long double and
_Float128 can get chosen. In particular, this applies to some
_Complex long double functions (where x happens to have type _Complex
long double, resulting in min_of_type returning a _Float128 value when
it should return a long double value). For some reason, this only
caused test failures for me on x86_64 with GCC 6 but not GCC 7 (I
suspect it triggers known bugs in conversions from x86 long double to
_Float128 that are present in GCC 6's soft-fp).
Tested for x86_64 (in conjunction with float128 patches).
* sysdeps/generic/math_private.h (__EXPR_FLT128): Do not apply
typeof to argument passed to __builtin_types_compatible_p.
(min_of_type): Pass type argument, not x, to __EXPR_FLT128.
| -rw-r--r-- | ChangeLog | 4 | ||||
| -rw-r--r-- | sysdeps/generic/math_private.h | 4 |
2 files changed, 6 insertions, 2 deletions
@@ -1,5 +1,9 @@ 2017-06-22 Joseph Myers <joseph@codesourcery.com> + * sysdeps/generic/math_private.h (__EXPR_FLT128): Do not apply + typeof to argument passed to __builtin_types_compatible_p. + (min_of_type): Pass type argument, not x, to __EXPR_FLT128. + * math/w_acos_template.c [__USE_WRAPPER_TEMPLATE]: Include <errno.h>. * math/w_acosh_template.c [__USE_WRAPPER_TEMPLATE]: Likewise. diff --git a/sysdeps/generic/math_private.h b/sysdeps/generic/math_private.h index 6ea5e25e5a..1418bbda27 100644 --- a/sysdeps/generic/math_private.h +++ b/sysdeps/generic/math_private.h @@ -304,7 +304,7 @@ extern void __docos (double __x, double __dx, double __v[]); #if __HAVE_DISTINCT_FLOAT128 # define __EXPR_FLT128(x, yes, no) \ __builtin_choose_expr (__builtin_types_compatible_p \ - (__typeof (x), long double), no, yes) + (x, long double), no, yes) #else # define __EXPR_FLT128(x, yes, no) no #endif @@ -318,7 +318,7 @@ extern void __docos (double __x, double __dx, double __v[]); __builtin_choose_expr \ (__builtin_types_compatible_p (type, double), \ DBL_MIN, \ - __EXPR_FLT128 (x, FLT128_MIN, LDBL_MIN))) + __EXPR_FLT128 (type, FLT128_MIN, LDBL_MIN))) /* If X (which is not a NaN) is subnormal, force an underflow exception. */ |