GoogleTest is packaged in subdirectory.

  ls -lah  downloads/googletest-release-1.11.0/*
    drwxrwxr-x 2 4.0K Jun 11  2021 ci
    drwxrwxr-x 8 4.0K Jun 11  2021 googlemock
    drwxrwxr-x 9 4.0K Jun 11  2021 googletest
    # ....

First download the zip file, then unzip to a tmp dir and finaly move googletest
to tools directory

This will ignore warning in gtest
since it is not compatible with some of the flags beeing enforced

  gtest.cc:1266:43:
  error: implicit conversion from ‘float’ to ‘double’ to match other
  operand of binary expression [-Werror=double-promotion]
   1266 |         costs[l_i + 1][r_i + 1] = replace + 1.00001;
        |                                   ~~~~~~~~^~~~~~~~~

Compile with -O1 to make inline functions compatible with gcc

  utils_math.c:582: undefined reference to `utils_truncate_number'
    error: ld returned 1 exit status

 Unused variable ret causes error :

 unittest.cpp: In member function ‘virtual void Saturate2dVector_ValsOnEdgeOfRange_Test::TestBody()’:
  unittest.cpp:291:9: error: variable ‘ret’ set but not used [-Werror=unused-but-set-variable]
    291 |    bool ret;
        |         ^~~