Where does gcc look for C and C++ header files?
You can create a file that attempts to include a bogus system header.If you run gcc in verbose mode on such a source, it will list all the system include locations as it looks for the bogus header.
$ echo "#include <bogus.h>" > t.c; gcc -v t.c; rm t.c[..]#include "..." search starts here:#include <...> search starts here: /usr/local/include /usr/lib/gcc/i686-apple-darwin9/4.0.1/include /usr/include /System/Library/Frameworks (framework directory) /Library/Frameworks (framework directory)End of search list.[..]t.c:1:32: error: bogus.h: No such file or directory