Add gcc -ftrack-macro-expansion

Feature request

GCC supports -ftrack-macro-expansion

[https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html](https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html)

Could clang support it too.

It would help keep options the same across builds.

Start by reading GCC's Preprocessor Options documentation for -ftrack-macro-expansion and locating clang's preprocessor option handling. No source file or test is named in the issue; done means clang accepts the option and provides compatible macro-expansion tracking behavior while preserving build-option compatibility.

Written by the indexing model from the issue text.