[PATCH] D49466: Initial implementation of -fmacro-prefix-map and -ffile-prefix-map

Fri Jan 11 06:33:19 PST 2019

dankm added a comment.

In D49466#1353437 <https://reviews.llvm.org/D49466#1353437>, @alxu wrote:

> FYI, according to my comment on D49652 <https://reviews.llvm.org/D49652>, assuming I checked it correctly, gcc applies the maps in reverse order of command line specification, not sorted order. It seems unlikely that anyone is actually depending on the order though.

Yeah, I noticed that, but it appears to be undefined by GCC's documentation. I agree with review D49652 <https://reviews.llvm.org/D49652>, but I also want to get this in before 8.0 branches, even if it's not ideal.

Right now we apply them in strict alphabetical order, switching to reverse order lets one map /objdir/<sysroot> to / while remapping /objdir/ to /some/other/dir, which is my use case.

Repository:
  rC Clang

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D49466/new/

https://reviews.llvm.org/D49466