hans added inline comments. ================ Comment at: include/clang/Driver/CLCompatOptions.td:68 @@ +67,3 @@ +def _SLASH_FC : CLFlag<"FC">, + HelpText<"Use absolute paths in diagnostics and __FILE__">, + Alias<fabsolute_paths>; ---------------- thakis wrote: > hans wrote: > > thakis wrote: > > > Hm, I'm not sure this should affect __FILE__. It sounds people want this > > > for diagnostics, but making it affect __FILE__ makes reproducible builds > > > harder. (There's -ffile-macro-prefix-to-remove from > > > http://reviews.llvm.org/D17741 for that too, but that's not in.) > > The MSVC docs say it applies to __FILE__ though > > https://msdn.microsoft.com/en-us/library/027c4t2s.aspx and I worry that > > implementing only half of it might surprise users. > > > > Chromium currently builds with MSVC and /FC, so we should already have full > > paths in __FILE__ there. > Sure, but the MSVC build is not deterministic in several ways that folks > aren't happy about, and we're supposed to improve that :-) > > As far as I know __FILE__ defaults to just the file's basename in cl.exe (is > that true?). So without /FC __FILE__ is useless there and people more or less > have to pass /FC. With clang, we emit the full relative path to the file, so > it's not useless already. > > For diagnostics, I can kind of see how full paths are useful: You likely > develop on the same machine as you see the diagnostics on, so people want > real absolute paths so they can click on them in MSVC. For __FILE__, that's > less convincing, since that gets embedded into the binary that's shipped > elsewhere. > As far as I know FILE defaults to just the file's basename in cl.exe (is that > true?).
In my testing, MSVC does include the full relative path in __FILE__ by default. I agree that diagnostics seems to be the main motivation here. I'm just worried that if we implement /FC but leave out the FILE part, that's confusing for whoever might rely on it. Maybe we should just do an -fabs-path-diagnostics option instead? https://reviews.llvm.org/D23816 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
