1 files changed, 2 insertions, 0 deletions
diff --git a/source/slang/slang-check-modifier.cpp b/source/slang/slang-check-modifier.cpp
index 7721fedbf..e91d2e45b 100644
--- a/source/slang/slang-check-modifier.cpp
+++ b/source/slang/slang-check-modifier.cpp
@@ -932,6 +932,8 @@ namespace Slang
                 }
             }
             requireCapAttr->capabilitySet = CapabilitySet(capabilityNames);
+            if (requireCapAttr->capabilitySet.isInvalid())
+                maybeDiagnose(getSink(), this->getOptionSet(), DiagnosticCategory::Capability, attr, Diagnostics::unexpectedCapability, attr, CapabilityName::Invalid);
         }
         else if (auto requirePreludeAttr = as<RequirePreludeAttribute>(attr))
         {