http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48524
--- Comment #2 from Ryan Hill <dirtyepic at gentoo dot org> 2011-04-09 18:51:20 UTC --- Sorry, i just wanted a trivial example. The actual rule we use is %{!D_FORTIFY_SOURCE:%{!D_FORTIFY_SOURCE=*:%{!U_FORTIFY_SOURCE:-D_FORTIFY_SOURCE=2}}} but this is just one example of several. The reason we use specs instead of just changing the default is so we can easily bypass them at runtime. This allows us, for example, to have a single compiler for both normal and hardened profiles. I understand what you're saying, but it still seems like an omission to me to not have a way to match switches with separate arguments. Surely this isn't the only case where this is useful?