With perl 5.10 from the perl-experimental overlay, the stable version of app-editors/nvi, 1.81.6-r2, fails to compile (at least with the perl use flag set) with:
../dist/../perl_api/../common/../ex/extern.h:90: error: conflicting types for 'Perl_re_compile'
Created attachment 206015 [details]
Created attachment 206017 [details]
emerge info output
With perl-5.10.1 from the main tree, I get a link error related to --as-needed (which went unnoticed with perl-5.8.x and which I'll fix), but no compile error. Is this specific to the perl 5.10 in the overlay?
Can't say so far whether this is reproducible with the portage tree version of perl - I'll give it a try on a non-perl-experimental machine...
Just tried app-editors/nvi-1.81.6-r3 from the portage tree, with identical result.
I'm getting the same results as you after trying on amd64, with perl 5.10 from the main tree. Summary adjusted.
Adjusting summary again... It's working with USE=ithreads because then re_compile gets defined as a function-like macro rather than an object-like macro, meaning there is no substitution in re_compile __P(...). I'm testing a fix.
Fixed now, and thanks for reporting.