build fails if CMAKE_C(XX)_FLAGS is not empty

[jhgoebbert]

Hi everyone,

If cmake is used to configure the build with a non-empty CMAKE_C_FLAGS (or CMAKE_CXX_FLAGS) like

cmake -DCMAKE_C_FLAGS:STRING='-O2' ..

xcodeeml-tools cannot handle that and the build fails:

[ 40%] Building C object F-FrontEnd/src/CMakeFiles/ffront.dir/C-expr-mem.c.o
cc: fatal error: no input files
compilation terminated.
/bin/sh: -Werror: command not found
make[2]: *** [F-FrontEnd/src/CMakeFiles/ffront.dir/build.make:93: F-FrontEnd/src/CMakeFiles/ffront.dir/C-expr-mem.c.o] Error 127
make[1]: *** [CMakeFiles/Makefile2:576: F-FrontEnd/src/CMakeFiles/ffront.dir/all] Error 2
make: *** [Makefile:136: all] Error 2