diff --git a/releasenotes.md b/releasenotes.md
index 3933b90ae..eb7ae66c6 100644
--- a/releasenotes.md
+++ b/releasenotes.md
@@ -25,6 +25,7 @@
 - Allow even smaller memory limits.
 - Check unaligned array access.
 - Add "@structlike" for typedefs.
+- "poison" the current function early when a declaration can't be correctly resolved.
 
 ### Fixes
 - mkdir/rmdir would not work properly with substring paths on non-windows platforms.
diff --git a/src/compiler/sema_decls.c b/src/compiler/sema_decls.c
index 3f028106e..26111e7b0 100755
--- a/src/compiler/sema_decls.c
+++ b/src/compiler/sema_decls.c
@@ -4639,6 +4639,7 @@ bool sema_analyse_var_decl(SemaContext *context, Decl *decl, bool local)
 
 	VarDeclKind kind = decl->var.kind;
 
+	bool success = true;
 	bool is_global = !local;
 	switch (kind)
 	{
@@ -4811,25 +4812,26 @@ bool sema_analyse_var_decl(SemaContext *context, Decl *decl, bool local)
 		CallEnvKind env_kind = context->call_env.kind;
 		if (is_static) context->call_env.kind = CALL_ENV_FUNCTION_STATIC;
 		decl->in_init = true;
-		if (!sema_expr_analyse_assign_right_side(context, NULL, decl->type, init, false, true, NULL))
-		{
-			context->call_env.kind = env_kind;
-			return decl_poison(decl);
-		}
+		success = sema_expr_analyse_assign_right_side(context, NULL, decl->type, init, false, true, NULL);
 		decl->in_init = false;
 		context->call_env.kind = env_kind;
-
 		if (infer_len)
 		{
+			if (!success) return decl_poison(decl);
 			decl->type = type_add_optional(init->type, IS_OPTIONAL(decl));
 		}
 
 		// 2. Check const-ness
-		if (global_level_var && !expr_is_runtime_const(init))
+		if (global_level_var)
 		{
-			SEMA_ERROR(init, "The expression must be a constant value.");
-			return decl_poison(decl);
+			if (!success) return decl_poison(decl);
+			if (!expr_is_runtime_const(init))
+			{
+				SEMA_ERROR(init, "The expression must be a constant value.");
+				return decl_poison(decl);
+			}
 		}
+		if (!success) goto EXIT_OK;
 		if (global_level_var || !type_is_abi_aggregate(init->type)) sema_cast_const(init);
 		if (expr_is_const(init))
 		{
@@ -4850,7 +4852,7 @@ bool sema_analyse_var_decl(SemaContext *context, Decl *decl, bool local)
 	{
 		if (!sema_set_alloca_alignment(context, decl->type, &decl->alignment)) return false;
 	}
-	return true;
+	return success;
 }
 
 
diff --git a/src/compiler/sema_stmts.c b/src/compiler/sema_stmts.c
index 785bacd24..40a4fabb5 100644
--- a/src/compiler/sema_stmts.c
+++ b/src/compiler/sema_stmts.c
@@ -1232,7 +1232,11 @@ static inline bool sema_analyse_declare_stmt(SemaContext *context, Ast *statemen
 	Decl *decl = statement->declare_stmt;
 	VarDeclKind kind = decl->var.kind;
 	bool erase = kind == VARDECL_LOCAL_CT_TYPE || kind == VARDECL_LOCAL_CT;
-	if (!sema_analyse_var_decl(context, decl, true)) return false;
+	if (!sema_analyse_var_decl(context, decl, true))
+	{
+		if (!decl_ok(decl)) context->active_scope.is_poisoned = true;
+		return false;
+	}
 	if (erase || decl->decl_kind == DECL_ERASED) statement->ast_kind = AST_NOP_STMT;
 	return true;
 }
@@ -1445,6 +1449,7 @@ static inline bool sema_analyse_for_stmt(SemaContext *context, Ast *statement)
 
 	if (is_infinite && !statement->for_stmt.flow.has_break)
 	{
+		if (!success) context->active_scope.is_poisoned = true;
 		SET_JUMP_END(context, statement);
 	}
 	return success;
diff --git a/test/src/test_suite_runner.c3 b/test/src/test_suite_runner.c3
index fdff8f522..da4331db4 100644
--- a/test/src/test_suite_runner.c3
+++ b/test/src/test_suite_runner.c3
@@ -442,7 +442,7 @@ fn void test_file(Path file_path)
 	// Start process
 	SubProcess compilation = process::create(cmdline.array_view(), { .search_user_path, .no_window, .inherit_environment })!!;
 	defer compilation.destroy();
-    CInt result = compilation.join()!!;
+    CInt result = compilation.join() ?? 1;
 	DString out;
 	io::copy_to(&&compilation.stderr(), &out)!!;
 	if (result != 0 && result != 1)
diff --git a/test/test_suite/cast/cast_struct.c3 b/test/test_suite/cast/cast_struct.c3
index 210ae5045..e60707a5a 100644
--- a/test/test_suite/cast/cast_struct.c3
+++ b/test/test_suite/cast/cast_struct.c3
@@ -25,13 +25,15 @@ struct BazTwo
 fn void test()
 {
     Foo x;
-    Bar y = (Bar)(x); // #error: 'Foo' to 'Bar'
+    { Bar y = (Bar)(x); } // #error: 'Foo' to 'Bar'
 
     Baz z;
-    int[2] w = (int[2])(z); // #error: 'Baz' to 'int[2]'
-    z = (Baz)(w);
-    BazTwo v = (BazTwo)(z); // #error: 'Baz' to 'BazTwo'
-    v = (BazTwo)(w);
-    z = (Baz)(v);
-    w = (int[2])(v);
+    { int[2] w = (int[2])(z); } // #error: 'Baz' to 'int[2]'
+    int[2] w;
+    z = (Baz)(w); // #error: to 'Baz'
+    { BazTwo v = (BazTwo)(z); } // #error: 'Baz' to 'BazTwo'
+    BazTwo v;
+    v = (BazTwo)(w); // #error: to 'BazTwo'
+    z = (Baz)(v);    // #error: possible to cast 'BazTwo' to 'Baz'
+    w = (int[2])(v); // #error: possible to cast 'BazTwo' to 'int[2]'
 }
diff --git a/test/test_suite/compile_time/concat_slice_array.c3 b/test/test_suite/compile_time/concat_slice_array.c3
index 1e4f6621a..acfd71a51 100644
--- a/test/test_suite/compile_time/concat_slice_array.c3
+++ b/test/test_suite/compile_time/concat_slice_array.c3
@@ -10,6 +10,18 @@ $foreach  $c : $chars:
         int $offset = ($c - $from) / BITS;
         int $rem = ($c - $from) % BITS;
         uint128 $value = $bitmap[$offset]; // #error: is out of range
+$endforeach
+}
+
+fn int main2()
+{
+ String $chars = "Abcd";
+ char $from = 2;
+ char[10] $bitmap = {};
+$foreach  $c : $chars:
+        int $offset = ($c - $from) / BITS;
+        int $rem = ($c - $from) % BITS;
+        uint128 $value = 1;
         $value |= 1ULL << $rem;
         $bitmap = $bitmap[:$offset] +++ $value +++ $bitmap[$offset+1..]; // #error: End index out of bounds
 $endforeach
diff --git a/test/test_suite/errors/rethrow_macro.c3 b/test/test_suite/errors/rethrow_macro.c3
index 2e9f12a46..2c3f381ce 100644
--- a/test/test_suite/errors/rethrow_macro.c3
+++ b/test/test_suite/errors/rethrow_macro.c3
@@ -1,14 +1,14 @@
 module testing;
 import std::io;
 
-macro char[] read(src, Allocator allocator, n)
+macro void read(src, Allocator allocator, n)
 {
     char* data = allocator::malloc_try(allocator, n)!; // #error: Rethrow is only allowed in macros
-    io::read_all(src, data[:n])!;
+    (void)io::read_all(src, data[:n]);
 }
 
 fn void main()
 {
     ByteReader br;
-    read(&br, allocator::temp(), 10);
+    read(&br, allocator::temp(), 10)!!;
 }
\ No newline at end of file
diff --git a/test/test_suite/visibility/recurse_private_import.c3 b/test/test_suite/visibility/recurse_private_import.c3
index 17d6bd825..822904e59 100644
--- a/test/test_suite/visibility/recurse_private_import.c3
+++ b/test/test_suite/visibility/recurse_private_import.c3
@@ -27,7 +27,7 @@ import abc @norecurse @public;
 
 fn int test()
 {
-	Abc x; // #error: is '@private'
+	{ Abc x; } // #error: is '@private'
 	abc::baz::test(); // #error: is '@private'
 	return 0;
 }
\ No newline at end of file