Commit Graph

3 Commits

Author SHA1 Message Date
John McCall 99ce6bfe28 Improve the -Wsign-compare heuristics:
* If the unsigned type is smaller than the signed type, never warn, because
    its value will not change when zero-extended to the larger type.
  * If we're testing for (in)equality, and the unsigned value is an integer
    constant whose sign bit is not set, never warn, because even though the
    signed value might change, it can't affect the result of the equality.

Also make the comparison test cases much more rigorous, and have them expose
the subtle differences between C and C++ here.

llvm-svn: 86242
2009-11-06 08:49:08 +00:00
Douglas Gregor 6af6c3ee56 Turn off -Wsign-compare warnings by default
llvm-svn: 86233
2009-11-06 05:24:12 +00:00
John McCall 1fa36b7cab Implement the conditional-operator part of -Wsign-compare. Turn
DiagnoseSignCompare into Sema::CheckSignCompare and call it from more places.

Add some enumerator tests.  These seem to expose some oddities in the
types we're converting C++ enumerators to;  in particular, they're converting
to unsigned before int, which seems to contradict 4.5 [conv.prom] p2.

Note to self: stop baiting Doug in my commit messages.

llvm-svn: 86128
2009-11-05 09:23:39 +00:00