On Thu, Oct 3, 2019 at 1:55 PM Vladislav Ivanishin <v...@ispras.ru> wrote: > > Hi! > > This series implements the -Wclobbered warning on GIMPLE in place of the > old RTL implementation. > > This cover letter contains a high-level explanation of what is going on > and why. The new implementation itself is in the patch 3. I will post > the details in the accompanying blurb. > > The most obvious benefit of doing it on GIMPLE is making this warning > independent of the specific register allocation decisions the RA makes. > I.e. if there is a possibility of a different compiler allocating a > variable to a register live through the setjmp call, but in the current > compilation it got spilled, the existing implementation does not give a > warning. > > So the new implementation strives to indicate as many potential errors > in the code as it can, not limited to the problems pertinent to this > compilation with this particular compiler. This is in line with > e.g. what Tom Lane (of PostgreSQL) expressed interest in seeing [1]. > > Also, in order to suppress spurious warnings, it is sometimes useful to > distinguish paths realizable after the second (and subsequent) returns > from setjmp vs. realizable only after the first return (see PR 21161). > The new implementation does that using a simple heuristic. > > All comments are appreciated. Is this OK for trunk?
-ENOPATCH > [1] https://bugzilla.redhat.com/show_bug.cgi?id=1185673#c5 > > Thanks, > Vlad
