As noted in PR33304, empty macro arguments can cause problems for ISO C90 compilers (solaris cc) as well as for older gcc versions like 2.8.1. Therefore I'd like to see cpp warn about these constructs either with -pedantic in C90 more and/or its own flag.
We should use this warning during bootstrap to keep the sources bootstrappable when using compilers that have this issue. We have to fix the existing cases before we do that though. -- Summary: We should warn about empty macro arguments Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: enhancement Priority: P3 Component: preprocessor AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ghazi at gcc dot gnu dot org BugsThisDependsOn: 33304 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33305