------- Comment #10 from ghazi at gcc dot gnu dot org 2008-04-15 01:36 ------- (In reply to comment #8) > I propose that we do the following: > - add a warning to the C/C++ frontends that isinf (x) CMP isinf (y) is > only well-defined for !isinf (x) && !isinf (y). > this doesn't result in a runtime penalty and informs people about the possible > problem in their code (it is non-portable).
IMHO the above warning would have limited coverage because there are other ways users can test the results of isinf that would run into the sign problem. > A different workaround would be to canonicalize the return value of isinf to > bool. Doesn't this change the interface defined by c99? -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35509