Recover instead of crashing on MS assembly when no target is loaded

It's possible to embed the frontend in applications that haven't initialized
backend targets so we need to handle this condition gracefully.

llvm-svn: 193685

diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td
index 774e9e9..a45e89e 100644 (file)
--- a/clang/include/clang/Basic/DiagnosticParseKinds.td
+++ b/clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -23,6 +23,8 @@ def err_asm_empty : Error<"__asm used with no assembly instructions">;
 def err_inline_ms_asm_parsing : Error<"%0">;
 def err_msasm_unsupported_arch : Error<
   "Unsupported architecture '%0' for MS-style inline assembly">;
+def err_msasm_unable_to_create_target : Error<
+  "MS-style inline assembly is not available: %0">;
 }
 
 let CategoryName = "Parse Issue" in {

diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp
index caf0011..2ff83cb 100644 (file)
--- a/clang/lib/Parse/ParseStmt.cpp
+++ b/clang/lib/Parse/ParseStmt.cpp
@@ -2104,9 +2104,15 @@ StmtResult Parser::ParseMicrosoftAsmStatement(SourceLocation AsmLoc) {
   if (UnsupportedArch)
     Diag(AsmLoc, diag::err_msasm_unsupported_arch) << TheTriple.getArchName();
     
+  std::string Error;
+  const std::string &TT = TheTriple.getTriple();
+  const llvm::Target *TheTarget = llvm::TargetRegistry::lookupTarget(TT, Error);
+  if (!TheTarget)
+    Diag(AsmLoc, diag::err_msasm_unable_to_create_target) << Error;
+
   // If we don't support assembly, or the assembly is empty, we don't
   // need to instantiate the AsmParser, etc.
-  if (UnsupportedArch || AsmToks.empty()) {
+  if (UnsupportedArch || !TheTarget || AsmToks.empty()) {
     return Actions.ActOnMSAsmStmt(AsmLoc, LBraceLoc, AsmToks, StringRef(),
                                   /*NumOutputs*/ 0, /*NumInputs*/ 0,
                                   ConstraintRefs, ClobberRefs, Exprs, EndLoc);
@@ -2118,11 +2124,6 @@ StmtResult Parser::ParseMicrosoftAsmStatement(SourceLocation AsmLoc) {
   if (buildMSAsmString(PP, AsmLoc, AsmToks, TokOffsets, AsmString))
     return StmtError();
 
-  // Find the target and create the target specific parser.
-  std::string Error;
-  const std::string &TT = TheTriple.getTriple();
-  const llvm::Target *TheTarget = llvm::TargetRegistry::lookupTarget(TT, Error);
-
   OwningPtr<llvm::MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TT));
   OwningPtr<llvm::MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TT));
   // Get the instruction descriptor.

diff --git a/clang/test/Index/ms-asm-no-target.cpp b/clang/test/Index/ms-asm-no-target.cpp
new file mode 100644 (file)
index 0000000..acc555b
--- /dev/null
+++ b/clang/test/Index/ms-asm-no-target.cpp
@@ -0,0 +1,9 @@
+// RUN: c-index-test -test-load-source all -triple x86_64-apple-darwin10 -fasm-blocks -Wno-microsoft %s 2>&1 | FileCheck %s
+
+// Test that we diagnose when the application hasn't initialized LLVM targets
+// supporting the MS-style inline asm parser.
+
+void Break() {
+  __asm { int 3 }
+}
+// CHECK: error: MS-style inline assembly is not available