[Bug gcov-profile/83616] New: [GCOV] The 'goto' statement in nested for loop leads the label is wrongly marked as not executed in gcov

["yangyibiao at nju dot edu.cn" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83616

            Bug ID: 83616
           Summary: [GCOV] The 'goto' statement in nested for loop leads
                    the label is wrongly marked as not executed in gcov
           Product: gcc
           Version: 7.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: gcov-profile
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yangyibiao at nju dot edu.cn
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/7/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 7.2.0-8ubuntu3'
--with-bugurl=file:///usr/share/doc/gcc-7/README.Bugs
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr
--with-gcc-major-version-only --program-suffix=-7
--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 --with-target-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 --without-cuda-driver
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 7.2.0 (Ubuntu 7.2.0-8ubuntu3) 

# cat small.c
int main()
{
    for (int i = 0; i <= 1; i++)
    {
        for (int j = 0; j <= 1; j++)
        {
            goto lbl;
        }
    }
lbl:
    return 0;
}

# gcc -fprofile-arcs -ftest-coverage small.c -w; ./a.out; gcov small.c; cat
small.c.gcov
File 'small.c'
Lines executed:83.33% of 6
Creating 'small.c.gcov'

        -:    0:Source:small.c
        -:    0:Graph:small.gcno
        -:    0:Data:small.gcda
        -:    0:Runs:1
        -:    0:Programs:1
        1:    1:int main()
        -:    2:{
        1:    3:    for (int i = 0; i <= 1; i++)
        -:    4:    {
        1:    5:        for (int j = 0; j <= 1; j++)
        -:    6:        {
        1:    7:            goto lbl;
        -:    8:        }
        -:    9:    }
    #####:   10:lbl:
        1:   11:    return 0;
        -:   12:}

Line #10 is wrongly marked as not executed.