build GCC and G++

1- clone GCC repository 2- add select branch 3- in the source folder you will find ./contrib/download_prerequisites  execute it to download dependencies

C++ GTest

install GTest with CMake https://google.github.io/googletest/quickstart-cmake.html first example EXPECT AND ASSERT ASSERT: Fails fast, aborting the current function. EXPECT: Continues after the failure.

C Libraries

stdlib double atof(const char *str)Converts the string pointed to, by the argument str to a floating-point number (type double). int atoi(const char *str)Converts the