Index: clang/lib/AST/ExprConstant.cpp
===================================================================
--- clang/lib/AST/ExprConstant.cpp
+++ clang/lib/AST/ExprConstant.cpp
@@ -5451,6 +5451,7 @@
       Success = false;
     } else if (!ForbiddenNullArgs.empty() &&
                ForbiddenNullArgs[I - Args.begin()] &&
+               ArgValues[I - Args.begin()].isLValue() &&
                ArgValues[I - Args.begin()].isNullPointer()) {
       Info.CCEDiag(*I, diag::note_non_null_attribute_failed);
       if (!Info.noteFailure())
Index: clang/test/SemaCXX/attr-nonnull.cpp
===================================================================
--- clang/test/SemaCXX/attr-nonnull.cpp
+++ clang/test/SemaCXX/attr-nonnull.cpp
@@ -77,10 +77,11 @@
 constexpr int i32 = f3(0, &c);
 
 __attribute__((nonnull(4))) __attribute__((nonnull)) //expected-error {{out of bounds}}
-constexpr int f4(const int*, const int*) {
+constexpr int f4(const int*, const int*, int) {
   return 0;
 }
-constexpr int i4 = f4(&c, 0); //expected-error {{constant expression}} expected-note {{null passed}}
-constexpr int i42 = f4(0, &c); //expected-error {{constant expression}} expected-note {{null passed}}
+constexpr int i4 = f4(&c, 0, 0); //expected-error {{constant expression}} expected-note {{null passed}}
+constexpr int i42 = f4(0, &c, 1); //expected-error {{constant expression}} expected-note {{null passed}}
+constexpr int i43 = f4(&c, &c, 0);
 
 }
\ No newline at end of file