[Clang] Added check for unexpanded pack in attribute [[assume]] (#91893)

Added a check for unexpanded parameter pack in attribute [[assume]].
Tested it with expected-error statements from clang fronted. 

This fixes #91232.

Author: azmat-y

clang/lib/Sema/SemaStmtAttr.cpp

@@ -670,6 +670,11 @@ ExprResult Sema::ActOnCXXAssumeAttr(Stmt *St, const ParsedAttr &A,
   }
 
   auto *Assumption = A.getArgAsExpr(0);
+
+  if (DiagnoseUnexpandedParameterPack(Assumption)) {
+    return ExprError();
+  }
+
   if (Assumption->getDependence() == ExprDependence::None) {
     ExprResult Res = BuildCXXAssumeExpr(Assumption, A.getAttrName(), Range);
     if (Res.isInvalid())

clang/test/SemaCXX/cxx23-assume.cpp

@@ -138,3 +138,8 @@ constexpr int foo() {
 }
 
 static_assert(foo() == 0);
+
+template <bool ...val>
+void f() {
+    [[assume(val)]]; // expected-error {{expression contains unexpanded parameter pack}}
+}