Comment 59 for bug 1847361

It was suggested to use -save-temps (thanks danpb) and comparing the -i files.

The following is from:
$ gcc -Iblock -I. -I/build/qemu-D0lqny/qemu-2.11+dfsg -I/build/qemu-D0lqny/qemu-2.11+dfsg/include -pthread -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -D_GNU_SOURCE -Wall -Wundef -ftrack-macro-expansion=8 -c -CC -save-temps -o file-posix.o ../block/file-posix.c

Attaching the two files shows a lot of differences, but without knowing what to look for it can be hard to just "read" them for an issue.