[clang] [Clang][OpenMP] throw compilation error instead of crash in Stmt::OMPScopeDirectiveClass case (#77535) (PR #84135)

[via cfe-commits]

https://github.com/Puellaquae created https://github.com/llvm/llvm-project/pull/84135

Change unstable assertion into compilation error, and add a test for it.

>From a2c88b0b615875d625b49e596886a0f5b32cf159 Mon Sep 17 00:00:00 2001
From: Puellaquae <shentukeqin at hotmail.com>
Date: Wed, 6 Mar 2024 05:22:08 +0000
Subject: [PATCH 1/2] [Clang][OpenMP] throw compilation error instead of crash
 in Stmt::OMPScopeDirectiveClass case (#77535)

---
 clang/lib/CodeGen/CGStmt.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp
index d0a3a716ad75e1..698986a3e49dd0 100644
--- a/clang/lib/CodeGen/CGStmt.cpp
+++ b/clang/lib/CodeGen/CGStmt.cpp
@@ -414,7 +414,8 @@ void CodeGenFunction::EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs) {
     CGM.ErrorUnsupported(S, "OpenMP dispatch directive");
     break;
   case Stmt::OMPScopeDirectiveClass:
-    llvm_unreachable("scope not supported with FE outlining");
+    CGM.ErrorUnsupported(S, "scope with FE outlining");
+    break;
   case Stmt::OMPMaskedDirectiveClass:
     EmitOMPMaskedDirective(cast<OMPMaskedDirective>(*S));
     break;

>From 52e4f0b996085b289d1550af06760e273c390996 Mon Sep 17 00:00:00 2001
From: Puellaquae <shentukeqin at hotmail.com>
Date: Wed, 6 Mar 2024 08:05:52 +0000
Subject: [PATCH 2/2] [Clang][OpenMP] add test for Stmt::OMPScopeDirectiveClass
 support error

---
 clang/test/OpenMP/error_unsupport_feature.c | 8 ++++++++
 1 file changed, 8 insertions(+)
 create mode 100644 clang/test/OpenMP/error_unsupport_feature.c

diff --git a/clang/test/OpenMP/error_unsupport_feature.c b/clang/test/OpenMP/error_unsupport_feature.c
new file mode 100644
index 00000000000000..a100300752db91
--- /dev/null
+++ b/clang/test/OpenMP/error_unsupport_feature.c
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -emit-obj -verify -fopenmp %s
+
+int main () {
+  int r = 0;
+#pragma omp scope reduction(+:r) // expected-error {{cannot compile this scope with FE outlining yet}}
+  r++;
+  return r;
+}