Fix regression with LLVM 13+: some errors in inline assembly don't stop compilation

Based on Luís' ldc-developers#4302; fixes ldc-developers#4293.

Author: kinke

CHANGELOG.md

@@ -8,6 +8,7 @@
 - Supports LLVM 9.0 - 15.0.
 
 #### Bug fixes
+- Fix regression with LLVM 13+: some errors in inline assembly don't stop compilation. (#4293, #4331)
 
 # LDC 1.31.0 (2022-02-11)
 

driver/codegenerator.cpp

@@ -161,8 +161,13 @@ bool inlineAsmDiagnostic(IRState *irs, const llvm::SMDiagnostic &d,
 #if LDC_LLVM_VER < 1300
 void inlineAsmDiagnosticHandler(const llvm::SMDiagnostic &d, void *context,
                                 unsigned locCookie) {
-  if (d.getKind() == llvm::SourceMgr::DK_Error)
+  if (d.getKind() == llvm::SourceMgr::DK_Error) {
     ++global.errors;
+  } else if (global.params.warnings == DIAGNOSTICerror &&
+             d.getKind() == llvm::SourceMgr::DK_Warning) {
+    ++global.warnings;
+  }
+
   inlineAsmDiagnostic(static_cast<IRState *>(context), d, locCookie);
 }
 #else
@@ -176,8 +181,15 @@ struct InlineAsmDiagnosticHandler : public llvm::DiagnosticHandler {
         return false;
 
     const auto &DISM = llvm::cast<llvm::DiagnosticInfoSrcMgr>(DI);
-    if (DISM.getKind() == llvm::SourceMgr::DK_Error)
+    if (DISM.getKind() == llvm::SourceMgr::DK_Error ||
+        DISM.getSeverity() == llvm::DS_Error) {
       ++global.errors;
+    } else if (global.params.warnings == DIAGNOSTICerror &&
+               (DISM.getKind() == llvm::SourceMgr::DK_Warning ||
+                DISM.getSeverity() == llvm::DS_Warning)) {
+      ++global.warnings;
+    }
+
     return inlineAsmDiagnostic(irs, DISM.getSMDiag(), DISM.getLocCookie());
   }
 };

tests/fail_compilation/asm_error_gh4293.d

@@ -0,0 +1,11 @@
+// Make sure an invalid asm instruction causes a non-zero exit code.
+
+// RUN: not %ldc -c %s 2> %t.stderr
+// RUN: FileCheck %s < %t.stderr
+
+void main()
+{
+    asm { "some_garbage"; }
+}
+
+// CHECK: asm_error_gh4293.d(8):1:2: error: invalid instruction mnemonic 'some_garbage'