https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82521
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2019-01-03
CC| |manu at gcc dot gnu.org,
| |msebor at gcc dot gnu.org
Summary|No -Wtype-limits warning |[7/8/9 Regression] No
|when using templates |-Wtype-limits warning when
| |using templates
Ever confirmed|0 |1
Known to fail| |5.4.0, 6.3.0, 7.3.0, 8.2.0,
| |9.0
--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
[Please include the full test case and GCC output in bug reports.]
Confirmed as a GCC 4.8 regression. GCC 4.7 issues -Wtype-limits for templates.
Bisection points to a revision in the range 124827 and 124899. I don't have
GCC binaries for all the revisions in the range but the likely culprit seems to
be r124856. I CC Manu for his thoughts.
2007-05-19 Manuel Lopez-Ibanez <m...@gcc.gnu.org>
* doc/invoke.texi (Warning Options): Add -Wconversion-sign.
(Wconversion): Update description.
(Wconversion-sign): New.
* c.opt (Wconversion-sign): New.
* c-opts.c (c_common_post_options): Uninitialized Wconversion-sign
means disabled for C++. Otherwise, take the status of Wconversion.
* c-common.c (conversion_warning): Warn with either Wconversion or
Wconversion-sign.
(warnings_for_convert_and_check): Conditions are already checked by
conversion_warning.
(convert_and_check): Don't check warnings if the conversion failed.
cp/
* cvt.c (cp_convert_and_check): Don't check warnings if the
conversion failed.
A simple test case and GCC output at r124825:
$ cat t.C && /opt/notnfs/gcc-bisect/obj/gcc/cc1plus.124825 -quiet -Wall -Werror
-o/dev/null t.C
template <typename T>
const char* f (T value)
{
return value == 12345U ? "-1" : "no";
}
const char *s = f<unsigned char>(0);
cc1plus.124825: warnings being treated as errors
t.C: In function ‘const char* f(T) [with T = unsigned char]’:
t.C:7: instantiated from here
t.C:4: error: comparison is always false due to limited range of data type
