[clang][Interp] Allow initialization of extern variables via ctors

tbaederr · tbaederr · commit 6484655f9dd0 · 2024-07-15T13:12:52.000+02:00
diff --git a/clang/lib/AST/Interp/Interp.cpp b/clang/lib/AST/Interp/Interp.cpp
@@ -248,7 +248,8 @@ bool CheckExtern(InterpState &S, CodePtr OpPC, const Pointer &Ptr) {
   if (!Ptr.isExtern())
     return true;
 
-  if (Ptr.isInitialized())
+  if (Ptr.isInitialized() ||
+      (Ptr.getDeclDesc()->asVarDecl() == S.EvaluatingDecl))
     return true;
 
   if (!S.checkingPotentialConstantExpression() && S.getLangOpts().CPlusPlus) {
diff --git a/clang/test/AST/Interp/literals.cpp b/clang/test/AST/Interp/literals.cpp
@@ -1232,6 +1232,13 @@ namespace Extern {
   }
   static_assert(&ExternNonLiteralVarDecl() == &nl, "");
 #endif
+
+  struct A {
+    int b;
+  };
+
+  extern constexpr A a{12};
+  static_assert(a.b == 12, "");
 }
 
 #if __cplusplus >= 201402L

Original file line number	Diff line number	Diff line change
`@@ -1232,6 +1232,13 @@ namespace Extern {`
`1232`	`1232`	`}`
`1233`	`1233`	`static_assert(&ExternNonLiteralVarDecl() == &nl, "");`
`1234`	`1234`	`#endif`
	`1235`	`+`
	`1236`	`+ struct A {`
	`1237`	`+ int b;`
	`1238`	`+ };`
	`1239`	`+`
	`1240`	`+ extern constexpr A a{12};`
	`1241`	`+ static_assert(a.b == 12, "");`
`1235`	`1242`	`}`
`1236`	`1243`
`1237`	`1244`	`#if __cplusplus >= 201402L`