https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120629
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |redi at gcc dot gnu.org
--- Comment #24 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I see a libstdc++ testsuite FAIL without LTO, which I bisected to
r16-1398-g8154fc95f097a1
make check RUNTESTFLAGS="conformance.exp=std/format/functions/format.cc
--target_board=unix/-D_GLIBCXX_USE_CXX11_ABI=0/-D_GLIBCXX_DEBUG"
The resulting executable segfaults in a member function of the COW std::string.
Reduced:
// { dg-options "-std=gnu++20 -O2" }
#define _GLIBCXX_USE_CXX11_ABI 0
#define _GLIBCXX_DEBUG 1
#include <format>
#include <string>
#include <assert.h>
int main()
{
using namespace std;
string s = format("{0}-{{", 8); // value of s is "8-{"
assert( s == "8-{" );
// align
{
char c = 120;
string sB = format("{:🤡^6}", "x");
assert( sB == "🤡🤡x🤡🤡🤡" );
string sC = format("{:*^6}", "🤡🤡🤡");
assert( sC == "🤡🤡🤡" );
}
}
The patch in comment 22 does fix it (the real testsuite FAIL and the reduced
version above).
