[clang][test] Specify value of -fopenmp=libomp for tests. (llvm#177239)

`libomp` is the default value when unconfigured in cmake, but llvm can
be configured to have `libgomp` be the default instead. Explicitly
specify this value so the test does not fail when it assumes libomp is
always the default.

Fix for f369d23 (llvm#150580)

Author: jyknight

clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp

@@ -4832,7 +4832,8 @@ TEST_P(ASTMatchersTest, OMPTargetUpdateDirective_From_HasClause) {
   )";
   EXPECT_TRUE(matchesWithOpenMP(Source0, Matcher));
 
-  auto astUnit = tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp"});
+  auto astUnit =
+      tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp=libomp"});
   ASSERT_TRUE(astUnit);
 
   auto Results = match(ompTargetUpdateDirective().bind("directive"),
@@ -4892,7 +4893,8 @@ TEST_P(ASTMatchersTest, OMPTargetUpdateDirective_From_ArraySection_NoStride) {
     }
   )";
 
-  auto astUnit = tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp"});
+  auto astUnit =
+      tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp=libomp"});
   ASSERT_TRUE(astUnit);
 
   auto Results = match(ompTargetUpdateDirective().bind("directive"),
@@ -4951,7 +4953,8 @@ TEST_P(ASTMatchersTest, OMPTargetUpdateDirective_To_HasClause) {
   )";
   EXPECT_TRUE(matchesWithOpenMP(Source0, Matcher));
 
-  auto astUnit = tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp"});
+  auto astUnit =
+      tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp=libomp"});
   ASSERT_TRUE(astUnit);
 
   auto Results = match(ompTargetUpdateDirective().bind("directive"),
@@ -5008,7 +5011,8 @@ TEST_P(ASTMatchersTest, OMPTargetUpdateDirective_To_ArraySection_NoStride) {
     }
   )";
 
-  auto astUnit = tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp"});
+  auto astUnit =
+      tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp=libomp"});
   ASSERT_TRUE(astUnit);
 
   auto Results = match(ompTargetUpdateDirective().bind("directive"),

clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp

@@ -2829,7 +2829,8 @@ TEST(ASTMatchersTestOpenMP, OMPFromClause) {
   )";
   EXPECT_TRUE(matchesWithOpenMP(Source0, Matcher));
 
-  auto astUnit = tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp"});
+  auto astUnit =
+      tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp=libomp"});
   ASSERT_TRUE(astUnit);
 
   auto Results = match(ompTargetUpdateDirective().bind("directive"),
@@ -2893,7 +2894,8 @@ TEST(ASTMatchersTestOpenMP, OMPToClause) {
   )";
   EXPECT_TRUE(matchesWithOpenMP(Source0, Matcher));
 
-  auto astUnit = tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp"});
+  auto astUnit =
+      tooling::buildASTFromCodeWithArgs(Source0, {"-fopenmp=libomp"});
   ASSERT_TRUE(astUnit);
 
   auto Results = match(ompTargetUpdateDirective().bind("directive"),