Fix crash with unsupported architectures in Linux/Gnu target triples.

Summary: This patch adds a check and an error message to gnutools::Linker::ConstructJob in case the architecture is not supported. For most other operating systems, the error message is created in lib/Basic/Targets.cpp:AllocateTarget, but when construction the linker arguments for the gnutools linker a supported architecture is required.

Reviewers: rafael, joerg, echristo

Subscribers: mehdi_amini, joerg, dschuff, cfe-commits

Differential Revision: https://reviews.llvm.org/D27066

llvm-svn: 288327

1 files changed, 8 insertions, 3 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 8760b85..757c0ce 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -9941,7 +9941,7 @@ static const char *getLDMOption(const llvm::Triple &T, const ArgList &Args) {
       return "elf32_x86_64";
     return "elf_x86_64";
   default:
-    llvm_unreachable("Unexpected arch");
+    return nullptr;
   }
 }
 
@@ -10014,8 +10014,13 @@ void gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("--eh-frame-hdr");
   }
 
-  CmdArgs.push_back("-m");
-  CmdArgs.push_back(getLDMOption(ToolChain.getTriple(), Args));
+  if (const char *LDMOption = getLDMOption(ToolChain.getTriple(), Args)) {
+    CmdArgs.push_back("-m");
+    CmdArgs.push_back(LDMOption);
+  } else {
+    D.Diag(diag::err_target_unknown_triple) << Triple.str();
+    return;
+  }
 
   if (Args.hasArg(options::OPT_static)) {
     if (Arch == llvm::Triple::arm || Arch == llvm::Triple::armeb ||