Allow multiple _AttributeTargets for attribute declaration (#4087)

The syntax like:
[__AttributeUsage(_AttributeTargets.Var)]
[__AttributeUsage(_AttributeTargets.Param)]
struct DefaultValueAttribute
{
    int iParam;
};

is allowed.

For user-defined attribute, we can specify more attribute targets on the
attribute declaration. So one attribute can be used in more than one
situations.

1 files changed, 8 insertions, 4 deletions

diff --git a/source/slang/slang-check-modifier.cpp b/source/slang/slang-check-modifier.cpp
index 56d905063..b8ff1a116 100644
--- a/source/slang/slang-check-modifier.cpp
+++ b/source/slang/slang-check-modifier.cpp
@@ -212,10 +212,14 @@ namespace Slang
         attrDecl->nameAndLoc.loc = structDecl->nameAndLoc.loc;
         attrDecl->loc = structDecl->loc;
 
-        AttributeTargetModifier* targetModifier = m_astBuilder->create<AttributeTargetModifier>();
-        targetModifier->syntaxClass = attrUsageAttr->targetSyntaxClass;
-        targetModifier->loc = attrUsageAttr->loc;
-        addModifier(attrDecl, targetModifier);
+        while(attrUsageAttr)
+        {
+            AttributeTargetModifier* targetModifier = m_astBuilder->create<AttributeTargetModifier>();
+            targetModifier->syntaxClass = attrUsageAttr->targetSyntaxClass;
+            targetModifier->loc = attrUsageAttr->loc;
+            addModifier(attrDecl, targetModifier);
+            attrUsageAttr = as<AttributeUsageAttribute>(attrUsageAttr->next);
+        }
 
         // Every attribute declaration is associated with the type
         // of syntax nodes it constructs (via reflection/RTTI).