Add "supported targets" in lld --help output to be compatible with what

libtool generated configure scripts expect.  Otherwise they might assume
shared libraries aren't supported.

From lld svn revisions 298568 and 298571.
Discussed with kettenis@

1 files changed, 13 insertions, 0 deletions

diff --git a/gnu/llvm/tools/lld/ELF/DriverUtils.cpp b/gnu/llvm/tools/lld/ELF/DriverUtils.cpp
index 803b112120d..5ba494d791d 100644
--- a/gnu/llvm/tools/lld/ELF/DriverUtils.cpp
+++ b/gnu/llvm/tools/lld/ELF/DriverUtils.cpp
@@ -120,6 +120,19 @@ opt::InputArgList ELFOptTable::parse(ArrayRef<const char *> Argv) {
 void elf::printHelp(const char *Argv0) {
   ELFOptTable Table;
   Table.PrintHelp(outs(), Argv0, "lld", false);
+  outs() << "\n";
+
+  // Scripts generated by Libtool versions up to at least 2.4.6 (the most
+  // recent version as of March 2017) expect /: supported targets:.* elf/
+  // in a message for the -help option. If it doesn't match, the scripts
+  // assume that the linker doesn't support very basic features such as
+  // shared libraries. Therefore, we need to print out at least "elf".
+  // Here, we print out all the targets that we support.
+  outs() << Argv0 << ": supported targets: "
+         << "elf32-i386 elf32-iamcu elf32-littlearm elf32-powerpc "
+         << "elf32-tradbigmips elf32-tradlittlemips elf32-x86-64 "
+         << "elf64-amdgpu elf64-littleaarch64 elf64-powerpc "
+         << "elf64-tradbigmips elf64-tradlittlemips elf64-x86-64\n";
 }
 
 // Reconstructs command line arguments so that so that you can re-run