[PATCH] D69985: Keep symbols passed by -init and -fini

Rui Ueyama via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Fri Nov 8 02:01:10 PST 2019


ruiu updated this revision to Diff 228385.
ruiu marked 2 inline comments as done.
ruiu added a comment.

- address review comments


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D69985/new/

https://reviews.llvm.org/D69985

Files:
  lld/ELF/Driver.cpp
  lld/test/ELF/lto/init-fini.ll


Index: lld/test/ELF/lto/init-fini.ll
===================================================================
--- /dev/null
+++ lld/test/ELF/lto/init-fini.ll
@@ -0,0 +1,46 @@
+; REQUIRES: x86
+; RUN: llvm-as %s -o %t.o
+
+;;
+;; Verify that symbols given by -init and -fini are preserved.
+;;
+
+; RUN: ld.lld -o %t.exe %t.o
+; RUN: llvm-nm %t.exe | FileCheck -check-prefix=TEST1 --allow-empty %s
+; RUN: llvm-readelf -d %t.exe
+
+; TEST1-NOT: foo
+; TEST1-NOT: bar
+
+; RUN: ld.lld -o %t.exe -init=foo -fini=bar %t.o
+; RUN: llvm-nm %t.exe | FileCheck -check-prefix=TEST2 %s
+
+; TEST2: bar
+; TEST2: foo
+
+;;
+;; Make sure that DT_INIT/DT_FINI are not created.
+;;
+
+; RUN: ld.lld -o %t.exe -shared %t.o
+; RUN: llvm-readelf -d %t.exe | FileCheck -check-prefix=TEST3 %s
+
+; TEST3-NOT: DT_INIT
+; TEST3-NOT: DT_FINI
+
+; RUN: ld.lld -o %t.exe -shared -init=foo -fini=bar -shared %t.o
+; RUN: llvm-readelf -d %t.exe | FileCheck -check-prefix=TEST4 %s
+
+; TEST4: INIT
+; TEST4: FINI
+
+target triple = "x86_64-unknown-linux-gnu"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+
+define void @foo() {
+  ret void
+}
+
+define void @bar() {
+  ret void
+}
Index: lld/ELF/Driver.cpp
===================================================================
--- lld/ELF/Driver.cpp
+++ lld/ELF/Driver.cpp
@@ -1782,6 +1782,12 @@
   for (StringRef pat : args::getStrings(args, OPT_undefined_glob))
     handleUndefinedGlob(pat);
 
+  // Mark -init and -fini symbols so that the LTO doesn't eliminate them.
+  if (Symbol *sym = symtab->find(config->init))
+    sym->isUsedInRegularObj = true;
+  if (Symbol *sym = symtab->find(config->fini))
+    sym->isUsedInRegularObj = true;
+
   // If any of our inputs are bitcode files, the LTO code generator may create
   // references to certain library functions that might not be explicit in the
   // bitcode file's symbol table. If any of those library functions are defined


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D69985.228385.patch
Type: text/x-patch
Size: 1953 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20191108/e60967ee/attachment.bin>


More information about the llvm-commits mailing list