On Thu, Aug 15, 2019 at 2:35 PM Thomas Koenig <tkoe...@netcologne.de> wrote: > > Hello world, > > this patch fixes PR 91443, in which we did not warn about a mismatched > external procedure. The problem was that the module this was called in > was resolved before parsing of the procedure ever started. > > The approach taken here is to move the checking of external procedures > to a stage after normal resolution. And, of course, fix the resulting > fallout from regression-testing :-) > There is also one policy change in the patch. Previously, we only warned > about mismatched declarations. Now, this is a hard error unless the > user specifies -std=legacy. The reason is that we have not yet solved > our single declaration problem, but it cannot be solved unless all > of a procedure's callers match. People who have such broken code > should at least be made aware that they have a problem. However, I would > like to have some sort of agreement on this point before the patch > is committed. This can also be changed (see the code at the bottom > of frontend-passes.c).
Personally, I'm fine with making this a hard error. As we've recently seen with the varargs & missing charlengths in LAPACK saga, mismatches can cause extremely subtle issues that can cause silent corruption and take an expert to figure out. > Once this is in, the next step is to issue errors for mismatching > calls where the callee is not in the same file. This can be done > with the infrastructure of this patch. > > So, OK for trunk? The patch itself looks Ok. One worry, are you introducing an O(N**2)(?) algorithm (looping over all symbols for every symbol?), and does this cause performance issues when compiling some gigantic F77 project? If this worry is unfounded, Ok for trunk. -- Janne Blomqvist
