Fix DeferredDiagnosticsEmitter for bug#45987

InOMPDeviceContext may be greater than 1. It needs to be clamp to 0 and 1
to be used as index for DoneMap.

clang/lib/Sema/Sema.cpp

@@ -1539,7 +1539,7 @@ public:
   }
 
   void checkFunc(SourceLocation Loc, FunctionDecl *FD) {
-    auto &Done = DoneMap[InOMPDeviceContext];
+    auto &Done = DoneMap[InOMPDeviceContext > 0 ? 1 : 0];
     FunctionDecl *Caller = UsePath.empty() ? nullptr : UsePath.back();
     if ((!ShouldEmitRootNode && !S.getLangOpts().OpenMP && !Caller) ||
         S.shouldIgnoreInHostDeviceCheck(FD) || InUsePath.count(FD))

clang/test/OpenMP/deferred-diags.cpp

@@ -0,0 +1,35 @@
+// RUN: %clang_cc1 -triple x86_64 -verify=expected,dev -std=c++11\
+// RUN:            -verify-ignore-unexpected=note \
+// RUN:            -fopenmp -fopenmp-version=50 -o - %s
+
+// expected-no-diagnostics
+
+// Test no infinite recursion in DeferredDiagnosticEmitter.
+constexpr int foo(int *x) {
+  return 0;
+}
+
+int a = foo(&a);
+
+// Test no crash when both caller and callee have target directives.
+int foo();
+
+class B {
+public:
+  void barB(int *isHost) {
+  #pragma omp target map(tofrom: isHost)
+     {
+       *isHost = foo();
+     }
+  }
+};
+
+class A : public B {
+public:
+  void barA(int *isHost) {
+  #pragma omp target map(tofrom: isHost)
+     {
+       barB(isHost);
+     }
+  }
+};