[PATCH] Warn for ignored ASM labels on typdef declarations

[Joseph Myers]

This patch is missing testcases, which need to be added to the testsuite 
for any such new feature, and when submitting a patch you should say 
explicitly in what configuration it was bootstrapped and tested without 
regressions.  Also, it's always incorrect to use -Wpedantic as the option 
controlling a warning that's not a warning about something not being part 
of the standard (since asm specifiers aren't part of the standard at all, 
it's thus wrong for -Wpedantic to control any diagnostic about them other 
than for them being used at all).

-- 
Joseph S. Myers
joseph@codesourcery.com