Accept absolute paths in the -fuse-ld option.

lib/Driver/ToolChain.cpp

@@ -341,19 +341,26 @@ std::string ToolChain::GetProgramPath(const char *Name) const {
 
 std::string ToolChain::GetLinkerPath() const {
   if (Arg *A = Args.getLastArg(options::OPT_fuse_ld_EQ)) {
-    StringRef Suffix = A->getValue();
-
-    // If we're passed -fuse-ld= with no argument, or with the argument ld,
-    // then use whatever the default system linker is.
-    if (Suffix.empty() || Suffix == "ld")
-      return GetProgramPath("ld");
-
-    llvm::SmallString<8> LinkerName("ld.");
-    LinkerName.append(Suffix);
-
-    std::string LinkerPath(GetProgramPath(LinkerName.c_str()));
-    if (llvm::sys::fs::exists(LinkerPath))
-      return LinkerPath;
+    StringRef UseLinker = A->getValue();
+
+    if (llvm::sys::path::is_absolute(UseLinker)) {
+      // If we're passed -fuse-ld= with what looks like an absolute path,
+      // don't attempt to second-guess that.
+      if (llvm::sys::fs::exists(UseLinker))
+        return UseLinker;
+    } else {
+      // If we're passed -fuse-ld= with no argument, or with the argument ld,
+      // then use whatever the default system linker is.
+      if (UseLinker.empty() || UseLinker == "ld")
+        return GetProgramPath("ld");
+
+      llvm::SmallString<8> LinkerName("ld.");
+      LinkerName.append(UseLinker);
+
+      std::string LinkerPath(GetProgramPath(LinkerName.c_str()));
+      if (llvm::sys::fs::exists(LinkerPath))
+        return LinkerPath;
+    }
 
     getDriver().Diag(diag::err_drv_invalid_linker_name) << A->getAsString(Args);
     return "";

test/Driver/fuse-ld.c

@@ -1,3 +1,9 @@
+// RUN: %clang %s -### \
+// RUN:     -fuse-ld=/usr/local/bin/or1k-linux-ld 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ABSOLUTE-LD
+// CHECK-ABSOLUTE-LD: /usr/local/bin/or1k-linux-ld
+
+
 // RUN: %clang %s -### \
 // RUN:     -target x86_64-unknown-freebsd 2>&1 \
 // RUN:   | FileCheck %s --check-prefix=CHECK-FREEBSD-LD