Regression, SIGSEGV instead of diagnostics when encountering bool operator==(const T&, const T&)

[Erfan-Ahmadi]

Description
SIGSEGV instead of diagnostics when encountering bool operator==(const T&, const T&)

Steps to reproduce:
Godbolt link: https://godbolt.org/z/5hsxeK5aE

[damyanp]

We also find that the compiler crashes in the non-spirv case as well, so we should have a look into this before declaring it spir-v specific.

[cassiebeckley]

Minimal reproducible example:

bool operator==(int lhs, int rhs) {
    return true;
}

void main() {}

[llvm-beanz]

The fix for this is pretty straightforward:

diff --git a/tools/clang/lib/Sema/SemaHLSL.cpp b/tools/clang/lib/Sema/SemaHLSL.cpp
index 31ff6a45851..704824c3822 100644
--- a/tools/clang/lib/Sema/SemaHLSL.cpp
+++ b/tools/clang/lib/Sema/SemaHLSL.cpp
@@ -15690,7 +15690,7 @@ void TryAddShaderAttrFromTargetProfile(Sema &S, FunctionDecl *FD,
 
   // if this FD isn't the entry point, then we shouldn't add
   // a shader attribute to this decl, so just return
-  if (EntryPointName != FD->getIdentifier()->getName()) {
+  if (FD->getIdentifier() && EntryPointName != FD->getIdentifier()->getName()) {
     return;
   }

We should craft some wider test cases too.