Index: src/CodeGen/CodeGenerator.cpp
===================================================================
--- src/CodeGen/CodeGenerator.cpp	(revision 4acd1f8c20515b87a7690e6ae07446619c94afa4)
+++ src/CodeGen/CodeGenerator.cpp	(revision 366f5cd47f06469e6c39617fdc1be75acd3f4943)
@@ -10,6 +10,6 @@
 // Created On       : Tue Oct 17 15:54:00 2023
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Wed Mar 11 11:13:10 2026
-// Update Count     : 28
+// Last Modified On : Tue Jun 23 13:42:15 2026
+// Update Count     : 34
 //
 
@@ -778,7 +778,6 @@
 
 void CodeGenerator::postvisit( ast::AlignofExpr const * expr ) {
-	// Using the GCC extension to avoid changing the std to C11.
-	extension( expr );
-	output << "__alignof__(";
+	extension( expr );
+	output << (expr->kind ? "__alignof__(" : "_Alignof(");
 	if ( auto type = expr->type.as<ast::TypeofType>() ) {
 		type->expr->accept( *visitor );
@@ -790,5 +789,5 @@
 
 void CodeGenerator::postvisit( ast::CountofExpr const * expr ) {
-	assertf( !options.genC, "CountofExpr should not reach code generation." );
+	assertf( ! options.genC, "CountofExpr should not reach code generation." );
 	extension( expr );
 	output << "countof(";