From 07f21ee31b5f427edb72d5578f713b3da3f3b96f Mon Sep 17 00:00:00 2001
From: ArielG-NV <159081215+ArielG-NV@users.noreply.github.com>
Date: Fri, 8 Aug 2025 13:19:25 -0700
Subject: Error if super-type capabilities are a super-set of sub-type (#7452)

Fixes: #7410

Changes:
1. super-type capabilities must be a super-set of sub-type capabilities
(and support the same shader stages/targets)
* InheritanceDecl visits super-type to inherit it's capabilities;
validate InheritanceDecl capabilities against sub-type
    * visit all container decl's with a default case
    * clean up functionDeclBase visitor
* Simplify `diagnoseUndeclaredCapability` by moving logic into
capability checking (more correct*)
3. added changed behavior to documentation
4. fixed some incorrect capabilities
5. **we do not** diagnose capability errors on interface
requirement-to-implementation if both lack explicit capability
requirements. This change is to work around a slangpy regression (test
case for the failing situation is in
`tests\language-feature\capability\capability-interface-extension-1.slang`),
Note: maybe for slang-2026 we don't do this?
6. requirement & implementation must support the same shader
stage/target. This was changed because otherwise we can have cases where
`X` inherits from `Y`, but `Y` is only expected to be used in `glsl`
whilst `X` is expected to be used in `hlsl | glsl`
7. removed
`tests/language-feature/capability/capabilitySimplification3.slang`
because it tests nothing special (redundant)

Note: not using rebase due to separate branches depending on this PR

---------

Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>
---
 source/slang/slang-parser.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'source/slang/slang-parser.cpp')

diff --git a/source/slang/slang-parser.cpp b/source/slang/slang-parser.cpp
index 7e9740b53..1302975df 100644
--- a/source/slang/slang-parser.cpp
+++ b/source/slang/slang-parser.cpp
@@ -5754,7 +5754,7 @@ static Stmt* parseTargetSwitchStmtImpl(Parser* parser, TargetSwitchStmt* stmt)
                         Diagnostics::unknownTargetName,
                         caseName.getContent());
                 }
-                targetCase->capability = int32_t(cap);
+                targetCase->capability = (int32_t)cap;
                 targetCase->capabilityToken = caseName;
                 targetCase->loc = caseName.loc;
                 targetCase->body = bodyStmt;
@@ -8743,7 +8743,7 @@ Expr* Parser::ParseLeafExpression()
 /// Parse an argument to an application of a generic
 static Expr* _parseGenericArg(Parser* parser)
 {
-    // The grammar for generic arguments needs to be a super-set of the
+    // The grammar for generic arguments needs to be a superset of the
     // grammar for types and for expressions, because we do not know
     // which to expect at each argument position during parsing.
     //
-- 
cgit v1.2.3