This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Turning warning "returning reference to temporary" into error?
Gabriel Dos Reis <gdr@integrable-solutions.net> writes:
> A compiler writer cannot imagine every possible usage. Which is why
> somethings are warnings. In this case, if the return value is ignored
> then the program is valid. GCC cannot reject it just because
> -pedantic is specified.
In other places where we can prove that execution of a certain code
path will cause undefined behavior, but we can't prove that that path
will be taken at runtime, we issue a warning and generate a trap
instruction. An analogous tactic for this scenario would be if we
generated code to return a distinguished pointer value that's
guaranteed to cause a segmentation fault when dereferenced. (This
should _not_ be 0, as that may mask the bug.)
zw