1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-24 11:42:57 +01:00
Go to file
Jordan Rupprecht 5a2178fb57 [llvm-objcopy] Skip --localize-symbol for undefined symbols
Summary:
Include the symbol being defined in the list of requirements for using --localize-symbol.

This is used, for example, when someone is depending on two different projects that have the same (or close enough) method defined in each library, and using "-L sym" for a conflicting symbol in one of the libraries so that the definition from the other one is used. However, the library may have internal references to the symbol, which cause program crashes when those are used, i.e.:

```
$ cat foo.c
int foo() { return 5; }
$ cat bar.c
int foo();
int bar() { return 2 * foo(); }
$ cat foo2.c
int foo() { /* Safer implementation */ return 42; }
$ cat main.c
int bar();
int main() {
  __builtin_printf("bar = %d\n", bar());
  return 0;
}
$ ar rcs libfoo.a foo.o bar.o
$ ar rcs libfoo2.a foo2.o
# Picks the wrong foo() impl
$ clang main.o -lfoo -lfoo2 -L. -o main
# Picks the right foo() impl
$ objcopy -L foo libfoo.a && clang main.o -lfoo -lfoo2 -L. -o main
# Links somehow, but crashes at runtime
$ llvm-objcopy -L foo libfoo.a && clang main.o -lfoo -lfoo2 -L. -o main
```

Reviewers: jhenderson, alexshap, jakehehrlich, espindola

Subscribers: emaste, arichardson

Differential Revision: https://reviews.llvm.org/D57417

llvm-svn: 352767
2019-01-31 16:45:16 +00:00
benchmarks Pull google/benchmark library to the LLVM tree 2018-08-28 09:42:41 +00:00
bindings Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
cmake Revert "[CMake] Unify scripts for generating VCS headers" 2019-01-31 07:12:43 +00:00
docs [libFuzzer] update docs 2019-01-31 01:47:29 +00:00
examples Fix some warnings on MSVC 2019-01-27 18:41:40 +00:00
include [PatternMatch] add special-case uaddo matching for increment-by-one 2019-01-31 16:40:07 +00:00
lib [ThinLTO] Rename COMDATs for COFF when promoting/renaming COMDAT leader 2019-01-31 16:00:15 +00:00
projects Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
resources
runtimes Revert "[CMake] Use __libc_start_main rather than fopen when checking for C library" 2019-01-28 19:26:41 +00:00
test [llvm-objcopy] Skip --localize-symbol for undefined symbols 2019-01-31 16:45:16 +00:00
tools [llvm-objcopy] Skip --localize-symbol for undefined symbols 2019-01-31 16:45:16 +00:00
unittests [CommandLine] Improve help text for cl::values style options 2019-01-31 13:58:48 +00:00
utils gn build: Merge r352483 2019-01-31 15:23:02 +00:00
.arcconfig
.clang-format
.clang-tidy
.gitattributes [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label. 2018-05-09 02:40:45 +00:00
.gitignore gitignore: ignore clangd index files. 2019-01-25 14:05:18 +00:00
CMakeLists.txt Revert "[CMake] Unify scripts for generating VCS headers" 2019-01-31 07:12:43 +00:00
CODE_OWNERS.TXT [llvm-mca] Move llvm-mca library to llvm/lib/MCA. 2018-12-17 08:08:31 +00:00
configure
CREDITS.TXT Remove a period from CREDITS.TXT (testing email change). NFC 2019-01-19 09:07:38 +00:00
LICENSE.TXT Fix typos throughout the license files that somehow I and my reviewers 2019-01-21 09:52:34 +00:00
llvm.spec.in Update structured references to the license to the new license. 2019-01-19 11:30:51 +00:00
LLVMBuild.txt Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
README.txt Test commit. 2018-09-22 01:01:03 +00:00
RELEASE_TESTERS.TXT Update the list of platforms & archs 2018-12-16 14:47:16 +00:00

The LLVM Compiler Infrastructure
================================

This directory and its subdirectories contain source code for LLVM,
a toolkit for the construction of highly optimized compilers,
optimizers, and runtime environments.

LLVM is open source software. You may freely distribute it under the terms of
the license agreement found in LICENSE.txt.

Please see the documentation provided in docs/ for further
assistance with LLVM, and in particular docs/GettingStarted.rst for getting
started with LLVM and docs/README.txt for an overview of LLVM's
documentation setup.

If you are writing a package for LLVM, see docs/Packaging.rst for our
suggestions.