From ef4f4bb25afa7ec0f656013f96ce7a260af9625f Mon Sep 17 00:00:00 2001
From: Janneke Nieuwenhuizen <janneke@gnu.org>
Date: Sat, 16 Sep 2023 08:19:00 +0200
Subject: [PATCH] squash! mescc: Fix switch statements' fallthrough --support
 mes

---
 module/mescc/compile.scm | 50 ++++++++++++++++++++++------------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/module/mescc/compile.scm b/module/mescc/compile.scm
index 071dfb67..20cc8e28 100644
--- a/module/mescc/compile.scm
+++ b/module/mescc/compile.scm
@@ -1791,29 +1791,33 @@
                  (set! i (1+ i)))
                n))))
 
-        (define (flatten-cases c)
-          (define (flatten-case case)
-            (pmatch case
-              ((case ,test (case . ,body))
-               (append `((case ,test (expr-stmt))) (flatten-case `(case ,@body))))
-              ((case ,test ,casebody (case . ,body))
-               (append `((case ,test ,casebody)) (flatten-case `(case ,@body))))
-              ((default (case . ,body))
-               (append `((default (expr-stmt))) (flatten-case `(case ,@body))))
-              ((default ,defbody (case . ,body))
-               (append `((default ,defbody)) (flatten-case `(case ,@body))))
-              ((case ,test (default . ,body))
-               (append `((case ,test (expr-stmt))) (flatten-case `(default ,@body))))
-              ((default ,rest)
-               (list case))
-              ((case ,test)
-               (list case))
-              ((case ,test ,expr)
-               (list case))
-              (,s (list s))))
-          (fold (lambda (x acc) (append acc (flatten-case x))) '() c))
-
-
+       (define (flatten-cases cases)
+         (define (flatten-case o cases)
+           (let ((c (pmatch o
+                      ((case ,test (case . ,body))
+                       (append `((case ,test (expr-stmt)))
+                               (flatten-case `(case ,@body))))
+                      ((case ,test ,case-body (case . ,body))
+                       (append `((case ,test ,case-body))
+                               (flatten-case `(case ,@body))))
+                      ((default (case . ,body))
+                       (append `((default (expr-stmt)))
+                               (flatten-case `(case ,@body))))
+                      ((default ,default-body (case . ,body))
+                       (append `((default ,default-body))
+                               (flatten-case `(case ,@body))))
+                      ((case ,test (default . ,body))
+                       (append `((case ,test (expr-stmt)))
+                               (flatten-case `(default ,@body))))
+                      ((default ,rest)
+                       (list o))
+                      ((case ,test)
+                       (list o))
+                      ((case ,test ,expr)
+                       (list o))
+                      (,s (list s)))))
+             (append c cases)))
+         (fold flatten-case '() cases))
 
        (let* ((info (append-text info (ast->comment `(switch ,expr (compd-stmt (block-item-list (ellipsis)))))))
               (statements (flatten-cases statements))