I came across the topic of the precompiled headers in C, so I started reading about it, in brief, the article(s) I read said that gcc will use precompiled header (h.gch) if there is one, otherwise normal header file(.h) will be used.
I just wanted to try it out and see if that actually happens with my code. So, I wanna know if there is any command in Linux(Ubuntu) to see what all files are being used by the GCC compiler while it is compiling your code. What I am thinking is, if the .h.gch file is used instead of .h files then it works how it should be and I get the concept of precompiled header files.
For example, if I do something like
gcc myCode.c
then gcc will definitely go to that file (myCode.c) and if myCode.c file includes a header file then that header file will also be touched/opened by gcc.
https://gcc.gnu.org/onlinedocs/gcc-5.1.0/gcc/Precompiled-Headers.html
This is from where I read about precompiled headers.