[clang][CUDA] Assume unknown emission status for skipped function definitions (#100124)

Emission status seems to be only used by cuda/openmp/hip compiles, to
figure out
when to emit diagnostics. Current logic emits "uknown" when definition
is
missing, so i extended that to skipped-function-bodies as well.

Author: kadircet

clang/lib/Sema/SemaDecl.cpp

@@ -20148,8 +20148,10 @@ Sema::FunctionEmissionStatus Sema::getEmissionStatus(const FunctionDecl *FD,
     // be emitted, because (say) the definition could include "inline".
     const FunctionDecl *Def = FD->getDefinition();
 
-    return Def && !isDiscardableGVALinkage(
-                      getASTContext().GetGVALinkageForFunction(Def));
+    // We can't compute linkage when we skip function bodies.
+    return Def && !Def->hasSkippedBody() &&
+           !isDiscardableGVALinkage(
+               getASTContext().GetGVALinkageForFunction(Def));
   };
 
   if (LangOpts.OpenMPIsTargetDevice) {

clang/unittests/Tooling/ToolingTest.cpp

@@ -586,6 +586,11 @@ TEST(runToolOnCode, TestSkipFunctionBody) {
   EXPECT_FALSE(runToolOnCodeWithArgs(
       std::make_unique<SkipBodyAction>(),
       "template<typename T> int skipMeNot() { an_error_here }", Args2));
+
+  EXPECT_TRUE(runToolOnCodeWithArgs(
+      std::make_unique<SkipBodyAction>(),
+      "__inline __attribute__((__gnu_inline__)) void skipMe() {}",
+      {"--cuda-host-only", "-nocudainc", "-xcuda"}));
 }
 
 TEST(runToolOnCodeWithArgs, TestNoDepFile) {