https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116853
Bug ID: 116853
Summary: [Regression 15] Bootstrap fails on *-darwin* after
r15-3859-g63a598deb0c9
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: iains at gcc dot gnu.org
CC: jason at gcc dot gnu.org, redi at gcc dot gnu.org
Target Milestone: ---
Three fails of the form:
/scratch/12-mon-rosetta/gcc-master/prev-x86_64-apple-darwin21/libstdc++-v3/include/bits/basic_string.h:4410:43:
error: argument of function call might be a candidate for a format attribute
[-Werror=suggest-attribute=format]
4410 | return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
4411 | "%f", __val);
| ~~~~~~~~~~~~
(line 4420 and 4430 the same).
This does not appear to be bogus - but in ext/string_conversions.h we have only
a template for this which does not accept the attribute.
I am testing the following work-around - but that might not be the preferred
solution:
diff --git a/libstdc++-v3/include/bits/basic_string.h
b/libstdc++-v3/include/bits/basic_string.h
index 976577f8f22..e9b17ea48b5 100644
--- a/libstdc++-v3/include/bits/basic_string.h
+++ b/libstdc++-v3/include/bits/basic_string.h
@@ -4399,6 +4399,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
return __str;
}
#elif _GLIBCXX_USE_C99_STDIO
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
// NB: (v)snprintf vs sprintf.
_GLIBCXX_NODISCARD
@@ -4430,6 +4432,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
"%Lf", __val);
}
+#pragma GCC diagnostic pop
#endif // _GLIBCXX_USE_C99_STDIO
#if defined(_GLIBCXX_USE_WCHAR_T) && _GLIBCXX_USE_C99_WCHAR
