[PATCH] D115040: [gn build] Build with Fission on non-mac non-win when using lld

[David Blaikie via Phabricator via llvm-commits]

dblaikie added a comment.

Cool!



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Comment at: llvm/utils/gn/build/BUILD.gn:85
+        #
+        # This requires `-Wl,--gdb-index` (above) to work well.
+        #
----------------
Yep, gdb relies on the index when using Split DWARF - without it you can expect a fair bit of uncertainty/variability in gdb about name lookup failures.


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Comment at: llvm/utils/gn/build/BUILD.gn:109-110
       # the flag here.
+      # Linetables always go in the .o file, even with -gsplit-dwarf, so there's
+      # no point in passing -gsplit-dwarf here.
     }
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Actually there can be some benefit to -g1/-gmlt even with Split DWARF - especially in optimized builds.

-g1 includes some debug info beyond the actual line table, needed to describe inlining - with split-dwarf that information can still be split out into the .dwo file and save some space/time for linking.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D115040/new/

https://reviews.llvm.org/D115040