Question

diff fails as the assembly listing is filled with slightly different labels.

Answer 1

Instead of directly comparing the assembly listings produced by the -S option, you could instead compile down to object files, disassemble the object files, and then compare those. (Or, you could just do a straight out diff of the hexdump of the compiled object code, but that’s much more painful). This gets rid of most labels, so it should make it easier to compare with diff. For example:

g++ file1.cc -c -o file1.o g++ file2.cc -c -o file2.o objdump -d file1.o > file1.s objdump -d file2.o > file2.s diff file1.s file2.s