boot2

commit db4d877362e9b952d72f15507e5e5fa481cd7b5d
parent 1609330a4c15372a20e6e3478499d792aaf66f9e
Author: Ryan Sepassi <rsepassi@gmail.com>
Date:   Sun, 26 Apr 2026 22:39:33 -0700

cc/cg: lock in p->x arrow access via cg fixture (§D.3)

cg-push-deref + cg-push-field already supported the indirect path:
the ptr-rval is push-deref'd to a struct lval (frame-indirect),
then cg-push-field's indirect-frame branch loads the address, adds
the field offset, and stashes it in a new indirect slot. The
fixture composes the existing primitives end-to-end so any
regression in either lands here.

Diffstat:
A
tests/cc-cg/38-arrow.expected-exit
 | 
1
+
A
tests/cc-cg/38-arrow.scm
 | 
59
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 60 insertions(+), 0 deletions(-)
diff --git a/tests/cc-cg/38-arrow.expected-exit b/tests/cc-cg/38-arrow.expected-exit
@@ -0,0 +1 @@
+5
diff --git a/tests/cc-cg/38-arrow.scm b/tests/cc-cg/38-arrow.scm
@@ -0,0 +1,59 @@
+;; tests/cc-cg/38-arrow.scm — pointer-to-struct field access via cg
+;; (§D.3 of docs/CC-PUNCHLIST.md). Models p->a / p->b through:
+;;   cg-push-sym sym-p     ; lval (frame), holds ptr-value
+;;   cg-load               ; rval ptr
+;;   cg-push-deref         ; lval struct (indirect)
+;;   cg-push-field "a"     ; lval int at p+0
+;;
+;;   struct S { int a; int b; }; struct S s;
+;;   struct S *p = &s; p->a = 4; p->b = 9; return p->b - p->a;
+;; (The cg fixture takes &s into a frame slot directly so we don't
+;; depend on parser-only address-of plumbing.)
+;;
+;; Expected: 9 - 4 == 5.
+
+(let* ((cg     (cg-init))
+       (st-ty  (%ctype 'struct 8 4
+                       (list "S" #t
+                             (list (list "a" %t-i32 0)
+                                   (list "b" %t-i32 4)))))
+       (pt-ty  (%ctype 'ptr 8 8 st-ty)))
+  (cg-fn-begin cg "main" '() %t-i32)
+  (let* ((off-s (cg-alloc-slot cg 8 4))
+         (off-p (cg-alloc-slot cg 8 8))
+         (sym-s (%sym "s" 'var 'auto st-ty off-s))
+         (sym-p (%sym "p" 'var 'auto pt-ty off-p)))
+    ;; p = &s
+    (cg-push-sym cg sym-p)
+    (cg-push-sym cg sym-s)
+    (cg-take-addr cg)
+    (cg-assign cg) (cg-pop cg)
+    ;; p->a = 4
+    (cg-push-sym cg sym-p)
+    (cg-load cg)
+    (cg-push-deref cg)
+    (cg-push-field cg "a")
+    (cg-push-imm cg %t-i32 4)
+    (cg-assign cg) (cg-pop cg)
+    ;; p->b = 9
+    (cg-push-sym cg sym-p)
+    (cg-load cg)
+    (cg-push-deref cg)
+    (cg-push-field cg "b")
+    (cg-push-imm cg %t-i32 9)
+    (cg-assign cg) (cg-pop cg)
+    ;; return p->b - p->a
+    (cg-push-sym cg sym-p)
+    (cg-load cg)
+    (cg-push-deref cg)
+    (cg-push-field cg "b")
+    (cg-load cg)
+    (cg-push-sym cg sym-p)
+    (cg-load cg)
+    (cg-push-deref cg)
+    (cg-push-field cg "a")
+    (cg-load cg)
+    (cg-binop cg 'sub)
+    (cg-return cg))
+  (cg-fn-end cg)
+  (write-bv-fd 1 (cg-finish cg)))