https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85245
--- Comment #1 from Yibiao Yang <yangyibiao at nju dot edu.cn> ---
(In reply to Yibiao Yang from comment #0)
> $ gcc -v
> Using built-in specs.
> COLLECT_GCC=gcc
> COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/8/lto-wrapper
> OFFLOAD_TARGET_NAMES=nvptx-none
> OFFLOAD_TARGET_DEFAULT=1
> Target: x86_64-linux-gnu
> Configured with: ../src/configure -v --with-pkgversion='Ubuntu
> 8-20170923-1ubuntu2' --with-bugurl=file:///usr/share/doc/gcc-8/README.Bugs
> --enable-languages=c,c++,go,brig,fortran,objc,obj-c++ --prefix=/usr
> --with-gcc-major-version-only --program-suffix=-8
> --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id
> --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
> --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
> --enable-libstdcxx-debug --enable-libstdcxx-time=yes
> --with-default-libstdcxx-abi=new --enable-gnu-unique-object
> --disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie
> --with-system-zlib --enable-objc-gc=auto --enable-multiarch --disable-werror
> --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32
> --enable-multilib --with-tune=generic --enable-offload-targets=nvptx-none
> --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
> --target=x86_64-linux-gnu
> Thread model: posix
> gcc version 8.0.0 20170923 (experimental) [trunk revision 253118] (Ubuntu
> 8-20170923-1ubuntu2)
>
>
> $ cat small.c
> int a=0;
> int main() {
> {
> int c[1];
> if (a < 1) {
> if (0)
> return 0;
> return 1;
> }
****************
****same bug****
for(;a<1;) {
if(0)
return 0;
return 1;
}
**** "return 0;" will also be marked as executed ****
***************
> }
> return 0;
> }
>
> $ gcc -w --coverage small.c; ./a.out; gcov-8 small.c; cat small.c.gcov
> File 'small.c'
> Lines executed:80.00% of 5
> Creating 'small.c.gcov'
>
> -: 0:Source:small.c
> -: 0:Graph:small.gcno
> -: 0:Data:small.gcda
> -: 0:Runs:1
> -: 0:Programs:1
> -: 1:int a=0;
> 1: 2:int main() {
> -: 3: {
> -: 4: int c[1];
> 1: 5: if (a < 1) {
> -: 6: if (0)
> 1: 7: return 0;
> 1: 8: return 1;
> -: 9: }
> -: 10: }
> #####: 11: return 0;
> -: 12:}
>
>
> Line #7 is wrongly marked as executed.
