If there was a mention of this change, I overlooked it.
The addition of -Wall to the $RPM_OPT_FLAGS value has some unintended
consequences. This broke my latest elfutils build until I worked around it.
The CFLAGS given to configure, i.e. what's in %optflags, is usually
appended to the package makefiles' own list of flags. As gcc processes its
command line, the later flags override the earlier ones. This is the right
thing e.g. when a package makefile uses -O and we override it to -O2 and so on.
When a package uses -W* flags already itself, it may use some -Wno-* flags
in its standard setting when some of the warnings are over-eager for some
of its code. For example, elfutils uses -Wall -Werror (and some more
warning options) on every file, but appends -Wno-format for a few files
where gcc's format checking is not smart enough to know what is really OK.
With the new redhat-rpm-config setting of %optflags including -Wall, we
wind up with -Wall -Werror -Wno-format -Wall -Wp,-D_FORTIFY_SOURCE=2 ...
and the second -Wall overrides the -Wno-format that overrode part of the
effect of the first -Wall. Since it uses -Werror, the additional spurious
warnings break the build.
There is an argument to be made that the upstream package is broken if you
cannot use "configure CFLAGS=-Wall". But, folks should be aware of this
change and how it might explain sudden differences in the builds of
packages that worked before Monday.
For today's elfutils build, I am using this: