drodriguez wrote: > But after taking a quick look, my impression is that this change reverses the > bug fixed in #70817. > > To recap, that PR preferred the C++ headers available in the toolchain > distribution over the SDK headers, when the compiler was launched via a > symbolic link to the executable (a behaviour common to the npm/xpm ecosystem). > > If I understand this proposal right (please correct me if I'm wrong), it will > move the SDK headers to the top of the list. > > If this will happen only when an explicit `-isysroot` is passed on the > compiler command line, it might be ok, but if it will happen for all cases, > this will simply bring us back to the pre 70817 case, when builds on old > macOS-es (like 10.13) with a new clang (like 17.x) will fail, due to the out > of sync old headers from the SDK with the new library from the toolchain. I > wasted quite a lot of time to diagnose this subtle issue by that time.
Yes. What I think Dmitry and I are trying to explain is that it is very weird that providing an explicit `-isysroot` in the command line is ignored for the C++ headers (and only for them). One can start using `-nostdinc` and friends, but that mean rebuilding the header search paths manually, which is not great. At least in my testing preferring the sysroot only happens when providing an explicit `-isysroot` in the command line, but also might be affected by the presence of `SDKROOT` in the environment (tools like `xcrun` set this value). If one is careful and avoid those two, the headers by the `clang` binary should be preferred. https://github.com/llvm/llvm-project/pull/80524 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
