Driver/Darwin: Pass -demangle when linking, if the linker supports it.

llvm-svn: 110873

2 files changed, 39 insertions, 0 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index cc00804a0ff..c1a16ea1771 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2262,6 +2262,22 @@ void darwin::Link::AddLinkArgs(const ArgList &Args,
                                ArgStringList &CmdArgs) const {
   const Driver &D = getToolChain().getDriver();
 
+  unsigned Version[3] = { 0, 0, 0 };
+  if (Arg *A = Args.getLastArg(options::OPT_mlinker_version_EQ)) {
+    bool HadExtra;
+    if (!Driver::GetReleaseVersion(A->getValue(Args), Version[0],
+                                   Version[1], Version[2], HadExtra) ||
+        HadExtra)
+      D.Diag(clang::diag::err_drv_invalid_version_number)
+        << A->getAsString(Args);
+  }
+
+  // Newer linkers support -demangle, pass it if supported and not disabled by
+  // the user.
+  if (Version[0] >= 100 && !Args.hasArg(options::OPT_Z_Xlinker__no_demangle)) {
+    CmdArgs.push_back("-demangle");
+  }
+
   // Derived from the "link" spec.
   Args.AddAllArgs(CmdArgs, options::OPT_static);
   if (!Args.hasArg(options::OPT_static))
diff --git a/clang/test/Driver/darwin-ld.c b/clang/test/Driver/darwin-ld.c
index 448446885a1..95e5b5febc4 100644
--- a/clang/test/Driver/darwin-ld.c
+++ b/clang/test/Driver/darwin-ld.c
@@ -82,3 +82,26 @@
 //
 // LINK_EXPLICIT_NO_PIE: ld"
 // LINK_EXPLICIT_NO_PIE: "-no_pie"
+
+// RUN: %clang -ccc-host-triple x86_64-apple-darwin10 -### %t.o \
+// RUN:   -mlinker-version=100 2> %t.log
+// RUN: FileCheck -check-prefix=LINK_NEWER_DEMANGLE %s < %t.log
+//
+// LINK_NEWER_DEMANGLE: ld"
+// LINK_NEWER_DEMANGLE: "-demangle"
+
+// RUN: %clang -ccc-host-triple x86_64-apple-darwin10 -### %t.o \
+// RUN:   -mlinker-version=100 -Wl,--no-demangle 2> %t.log
+// RUN: FileCheck -check-prefix=LINK_NEWER_NODEMANGLE %s < %t.log
+//
+// LINK_NEWER_NODEMANGLE: ld"
+// LINK_NEWER_NODEMANGLE-NOT: "-demangle"
+// LINK_NEWER_NODEMANGLE: "-lgcc"
+
+// RUN: %clang -ccc-host-triple x86_64-apple-darwin10 -### %t.o \
+// RUN:   -mlinker-version=95 2> %t.log
+// RUN: FileCheck -check-prefix=LINK_OLDER_NODEMANGLE %s < %t.log
+//
+// LINK_OLDER_NODEMANGLE: ld"
+// LINK_OLDER_NODEMANGLE-NOT: "-demangle"
+// LINK_OLDER_NODEMANGLE: "-lgcc"