[clang] [llvm] [Clang] [OpenMP] Support NOWAIT with optional argument (PR #128742)

[Michael Klemm via llvm-commits]

================
@@ -8,11 +8,11 @@ int main(int argc, char **argv) {
   #pragma omp nowait target update to(i) // expected-error {{expected an OpenMP directive}}
   #pragma omp target nowait update to(i) // expected-error {{unexpected OpenMP clause 'update' in directive '#pragma omp target'}} expected-error {{unexpected OpenMP clause 'to' in directive '#pragma omp target'}}
   {}
-  #pragma omp target update nowait() to(i) // expected-warning {{extra tokens at the end of '#pragma omp target update' are ignored}} expected-error {{expected at least one 'to' clause or 'from' clause specified to '#pragma omp target update'}}
-  #pragma omp target update to(i) nowait( // expected-warning {{extra tokens at the end of '#pragma omp target update' are ignored}}
+  #pragma omp target update nowait() to(i)  //  expected-error {{expected expression}} 
+  #pragma omp target update to(i) nowait(  //  expected-error {{expected expression}} //  expected-error {{expected ')'}} // expected-note {{to match this '('}}
   #pragma omp target update to(i) nowait (argc)) // expected-warning {{extra tokens at the end of '#pragma omp target update' are ignored}}
   #pragma omp target update to(i) nowait device (-10u)
-  #pragma omp target update to(i) nowait (3.14) device (-10u) // expected-warning {{extra tokens at the end of '#pragma omp target update' are ignored}}
+  #pragma omp target update to(i) nowait (3.14) device (-10u) // expected-error {{arguments of OpenMP clause 'nowait' with bitwise operators cannot be of floating type}}
----------------
mjklemm wrote:

```suggestion
  #pragma omp target update to(i) nowait (3.14) device (-10u) // expected-error {{arguments of OpenMP clause 'nowait' with bitwise operators cannot be of floating-point type}}
```

https://github.com/llvm/llvm-project/pull/128742