[Bug c++/96954] New: gcc times out with -O2/-O3/-Os

[tangyixuan at mail dot dlut.edu.cn]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96954

            Bug ID: 96954
           Summary: gcc times out with -O2/-O3/-Os
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tangyixuan at mail dot dlut.edu.cn
  Target Milestone: ---

Hi, gcc times out during execution of ./a.out with -O2/-O3/-Os:

$ cat s.cpp

template < class A > int B ( const A &){
        int a = B ( a );
        return a ;
}
int main (){ return B (0);}

$ g++ -O2 1337-2-runtime-out.C && ./a.out
times out

$ g++ -O0 1337-2-runtime-out.C && ./a.out
Segmentation fault (core dumped)

$ g++ -v
Using built-in specs.
COLLECT_GCC=/usr/local/gcc-20200823/bin/g++
COLLECT_LTO_WRAPPER=/usr/local/gcc-20200823/libexec/gcc/x86_64-pc-linux-gnu/11.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-11-20200823/configure --prefix=/usr/local/gcc-20200823
--enable-checking=release --enable-languages=c,c++ --disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.0.0 20200823 (experimental) (GCC)