Question

Is it possible to generate preprocessor output and compilation in one step with GCC?

Something like:

gcc -E -c main.cc -o main.o

that would generate main.o and main.i

Answer 1

Yes.

Look at gcc -save-temps option.

It compiles the source file and saves the result of the preprocessing in a .i file. (It also saves the result of the assembler phase to a .s file).

gcc -save-temps -c main.cc -o main.o

will generate main.o but also main.i and main.s.

main.i is the result of the preprocessing.