- When encountering a foreach over a ZString* it would not properly emit a compilation error, but hit an assert #2573.

releasenotes.md

@@ -20,6 +20,7 @@
 - Compiler assert with const enum based on vector #2566
 - Fix to `Path` handling `c:\foo` and `\home` parent. #2569
 - Fix appending to `c:\` or `\` #2569.
+- When encountering a foreach over a `ZString*` it would not properly emit a compilation error, but hit an assert #2573.
 
 ### Stdlib changes
 

src/compiler/sema_stmts.c

@@ -1546,6 +1546,7 @@ static inline bool sema_analyse_foreach_stmt(SemaContext *context, Ast *statemen
 		RETURN_SEMA_ERROR(var, "Add an explicit type to the variable if you want to iterate over an initializer list.");
 	}
 
+	Type *original_type = enumerator->type;
 	// In the case of a single `*`, then we will implicitly dereference that pointer.
 	if (canonical->type_kind == TYPE_POINTER)
 	{
@@ -1555,6 +1556,7 @@ static inline bool sema_analyse_foreach_stmt(SemaContext *context, Ast *statemen
 			RETURN_SEMA_ERROR(enumerator, "It is not possible to enumerate an expression of type %s.", type_quoted_error_string(enumerator->type));
 		}
 		if (!sema_expr_rewrite_insert_deref(context, enumerator)) return false;
+		canonical = enumerator->type->canonical;
 	}
 
 	// At this point we should have dereferenced any pointer or bailed.
@@ -1600,7 +1602,7 @@ static inline bool sema_analyse_foreach_stmt(SemaContext *context, Ast *statemen
 			if (value_type) goto SKIP_OVERLOAD;
 
 			// Otherwise this is an error.
-			RETURN_SEMA_ERROR(enumerator, "It's not possible to enumerate an expression of type %s.", type_quoted_error_string(enumerator->type));
+			RETURN_SEMA_ERROR(enumerator, "It's not possible to enumerate an expression of type %s.", type_quoted_error_string(original_type));
 		}
 		// If we want the value "by ref" and there isn't a &[], then this is an error.
 		if (!by_ref && value_by_ref)

test/test_suite/statements/foreach_zstring.c3

@@ -0,0 +1,9 @@
+module get_environ;
+import std;
+
+fn void main(String[] args)
+{
+    ZString* environ_arr = std::os::posix::environ;
+    foreach (idx, ZString &envvar : environ_arr) // #error: It's not possible to enumerate an expression of type 'ZString*'
+    {}
+}