consolidate the error messages.

Author: s-perron

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -12919,16 +12919,9 @@ def err_spirv_enum_not_int : Error<
 def err_spirv_enum_not_valid : Error<
    "invalid value for %select{storage class}0 argument">;
 
-def err_specialization_const_lit_init
-    : Error<"variable with 'vk::constant_id' attribute must be initialized by a int/float/enum/bool literal.">;
-def err_specialization_const_missing_initializer
-    : Error<
-          "variable with 'vk::constant_id' attribute must have an initializer">;
-def err_specialization_const_missing_const
-    : Error<"variable with 'vk::constant_id' attribute must be const">;
-def err_specialization_const_is_not_int_or_float
-    : Error<"variable with 'vk::constant_id' attribute must be an enum, bool, "
-            "integer, or floating point value">;
+def err_specialization_const
+    : Error<"variable with 'vk::constant_id' attribute must be a const "
+            "int/float/enum/bool and be initialized with a literal">;
 
 // errors of expect.with.probability
 def err_probability_not_constant_float : Error<

clang/lib/Sema/SemaDecl.cpp

@@ -14223,8 +14223,7 @@ void Sema::ActOnUninitializedDecl(Decl *RealDecl) {
 
     // HLSL variable with the `vk::constant_id` attribute must be initialized.
     if (!Var->isInvalidDecl() && Var->hasAttr<HLSLVkConstantIdAttr>()) {
-      Diag(Var->getLocation(),
-           diag::err_specialization_const_missing_initializer);
+      Diag(Var->getLocation(), diag::err_specialization_const);
       Var->setInvalidDecl();
       return;
     }

clang/lib/Sema/SemaHLSL.cpp

@@ -654,12 +654,12 @@ SemaHLSL::mergeVkConstantIdAttr(Decl *D, const AttributeCommonInfo &AL,
   auto *VD = cast<VarDecl>(D);
 
   if (getSpecConstBuiltinId(VD->getType()) == Builtin::NotBuiltin) {
-    Diag(VD->getLocation(), diag::err_specialization_const_is_not_int_or_float);
+    Diag(VD->getLocation(), diag::err_specialization_const);
     return nullptr;
   }
 
   if (!VD->getType().isConstQualified()) {
-    Diag(VD->getLocation(), diag::err_specialization_const_missing_const);
+    Diag(VD->getLocation(), diag::err_specialization_const);
     return nullptr;
   }
 
@@ -3735,7 +3735,7 @@ bool SemaHLSL::handleInitialization(VarDecl *VDecl, Expr *&Init) {
 
   APValue InitValue;
   if (!Init->isCXX11ConstantExpr(Context, &InitValue)) {
-    Diag(VDecl->getLocation(), diag::err_specialization_const_lit_init);
+    Diag(VDecl->getLocation(), diag::err_specialization_const);
     VDecl->setInvalidDecl();
     return false;
   }

clang/test/SemaHLSL/vk.spec-constant.error.hlsl

@@ -8,23 +8,23 @@
 const bool sc0 = true;
 
 #ifdef __spirv__
-// expected-error@+2{{variable with 'vk::constant_id' attribute cannot have an initializer that is not a literal}}
+// expected-error@+2{{variable with 'vk::constant_id' attribute must be a const int/float/enum/bool and be initialized with a literal}}
 [[vk::constant_id(1)]]
 const bool sc1 = sc0; // error
 
 // expected-warning@+1{{'constant_id' attribute only applies to external global variables}}
 [[vk::constant_id(2)]]
 static const bool sc2 = false; // error
 
-// expected-error@+2{{variable with 'vk::constant_id' attribute must have an initializer}}
+// expected-error@+2{{variable with 'vk::constant_id' attribute must be a const int/float/enum/bool and be initialized with a literal}}
 [[vk::constant_id(3)]]
 const bool sc3; // error
 
-// expected-error@+2{{variable with 'vk::constant_id' attribute must be const}}
+// expected-error@+2{{variable with 'vk::constant_id' attribute must be a const int/float/enum/bool and be initialized with a literal}}
 [[vk::constant_id(4)]]
 bool sc4 = false; // error
 
-// expected-error@+2{{variable with 'vk::constant_id' attribute must be an enum, bool, integer, or floating point value}}
+// expected-error@+2{{variable with 'vk::constant_id' attribute must be a const int/float/enum/bool and be initialized with a literal}}
 [[vk::constant_id(5)]]
 const int2 sc5 = {0,0}; // error