Hi,
As per GCC Documentation (
https://gcc.gnu.org/onlinedocs/cpp/Search-Path.html) if you do not instruct GCC otherwise,
it will look for headers
requested with
#include <file> in:
/usr/local/include
libdir/gcc/target/version/include
/usr/target/include
/usr/include
You can very well prioritize header file lookup to your path via -I<path of header> flag during compilation.
Another option is to provide --sysroot=<path to sysroot> in order to lookup system headers in your own
sysroot.
Command cpp -v will show you the look up process of header file.