I have been looking and looking until my eyes have started to cross. Here's my problem.
The only way I have been able to affect an entire build of GCC, for example in order to do a "-ggdb -O0" build of the entire compiler and its libraries, has been to do something like this: mkdir build cd build CFLAGS="-ggdb -O0" CXXFLAGS="-ggdb - O0" ../configure ... However, one thing I want to be able to do when developing the COBOL front end is: CXXFLAGS="-ggdb -O0 -std=C++17" ../configure ... That results in a build failure because libcody gets upset when the standard isn't c++11 Okay. So, I tried setting CXXFLAGS_FOR_BUILD, which as far as I know is not supposed to affect libraries. Jumping ahead a bit, I tried this: CXXFLAGS_FOR_BUILD="-DDUBNER_HARMLESS" I then did a complete --disable-bootstrap build and saved the output of the make. The text DUBNER_HARMLESS did not appear anywhere in the output. I have determined that the environment variable CXXFLAGS_FOR_BUILD="-DDUBNER_HARMLESS" is definitely present at the point where gcc/cobol/xxxx.cc files are being compiled. But it's not finding its way into the command line for the compilation. This raises two, presumably related, questions. 1) What is CXXFLAGS_FOR_BUILD supposed to be doing? 2) How can I set compilation switches for gcc stuff (like the gcc/cobol front end) without affecting lib*** stuff? Thanks.