[PATCH] D86142: [LLD] Search archives for non-tentative defintions.

[Fangrui Song via Phabricator via llvm-commits]

MaskRay added inline comments.


================
Comment at: lld/ELF/InputFiles.cpp:1240
+// The handling of tentative definitions (COMMON symbols) in archives is murky.
+// A tetative defintion will be promoted to a global definition if there are no
+// non-tentative definitions to dominate it. When we hold a tentative definition
----------------
typo: tentative


================
Comment at: lld/ELF/InputFiles.cpp:1249
+//    definition. An archive member would only be included if it satisfies some
+//    other undefined symbol. This is the behavior GOLD uses.
+//
----------------
GOLD -> Gold or gold


================
Comment at: lld/ELF/InputFiles.cpp:1254
+//    The linker searches archive memebers for global or weak definitions to
+//    replace the tentative definition with. This is the behavior used by BFD.
+//
----------------
BFD-> GNU ld


================
Comment at: lld/ELF/Options.td:68
+defm fortran_common : BB<"fortran-common",
+    "Search archive members for defintions to override COMMON symbols (default)",
+    " Do not search archive members for defintions to override COMMON symbols">;
----------------



================
Comment at: lld/ELF/Options.td:69
+    "Search archive members for defintions to override COMMON symbols (default)",
+    " Do not search archive members for defintions to override COMMON symbols">;
+
----------------



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Comment at: lld/ELF/Symbols.cpp:698
+static void replaceCommon(Symbol &oldSym, const LazyT &newSym) {
+  backwardReferences.erase(&oldSym);
+  oldSym.replace(newSym);
----------------
Do you have a `--warn-backrefs` test for `backwardReferences.erase(&oldSym);` ?


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Comment at: lld/test/ELF/common-archive-lookup.s:7
+
+# Object files.
+# RUN: llvm-mc -triple=powerpc64le -filetype=obj ref.s -o %t1.o
----------------
##


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Comment at: lld/test/ELF/common-archive-lookup.s:20
+
+# Bitcode files.
+# RUN: llvm-as -o %t1.bc commonblock.ll
----------------
##


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Comment at: lld/test/ELF/common-archive-lookup.s:112
+
+# Tentative definition of 'block'.
+  .comm block,40,8
----------------
##


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D86142/new/

https://reviews.llvm.org/D86142