From 3a6eb921b50e191468d29c233718657f9f85d68e Mon Sep 17 00:00:00 2001
From: _ov4 <ov4@ov4.org>
Date: Thu, 22 Oct 2026 13:45:36 +0000
Subject: feat(codegen): pass C-struct records by value

EXTERN parameters may now be C-struct records by value. clang's
arrangement decides the passing: coerced through memory, flattened
into elements, or indirect as byval or a pointer to a copy. Returning a
record by value stays rejected for now.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 tests/i/extern-c-struct-value/program.cps | 57 +++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 tests/i/extern-c-struct-value/program.cps

(limited to 'tests/i/extern-c-struct-value/program.cps')

diff --git a/tests/i/extern-c-struct-value/program.cps b/tests/i/extern-c-struct-value/program.cps
new file mode 100644
index 0000000..9db6319
--- /dev/null
+++ b/tests/i/extern-c-struct-value/program.cps
@@ -0,0 +1,57 @@
+// Records whose fields are C types pass to C functions by value.
+INCLUDE_OBJ "lib.o"
+TYPE CShort = C_TYPE("short")
+TYPE CFloat = C_TYPE("float")
+TYPE CLongLong = C_TYPE("long long")
+TYPE Pair
+    DECLARE A : C_INT
+    DECLARE B : C_INT
+ENDTYPE
+TYPE Vec2
+    DECLARE X : C_DOUBLE
+    DECLARE Y : C_DOUBLE
+ENDTYPE
+TYPE Mixed
+    DECLARE Tag : C_CHAR
+    DECLARE Value : C_DOUBLE
+    DECLARE Count : C_INT
+ENDTYPE
+TYPE Vec3f
+    DECLARE X : CFloat
+    DECLARE Y : CFloat
+    DECLARE Z : CFloat
+ENDTYPE
+TYPE Wide
+    DECLARE Lo : CLongLong
+    DECLARE Hi : CLongLong
+ENDTYPE
+EXTERN "C" EXTERN_FUNCTION pair_sum(Pair) RETURNS C_INT
+EXTERN "C" EXTERN_FUNCTION vec2_dot(Vec2, Vec2) RETURNS C_DOUBLE
+EXTERN "C" EXTERN_FUNCTION mixed_score(CShort, Mixed, C_INT) RETURNS C_DOUBLE
+EXTERN "C" EXTERN_FUNCTION vec3f_sum(Vec3f) RETURNS C_DOUBLE
+EXTERN "C" EXTERN_FUNCTION wide_after_five(C_INT, C_INT, C_INT, C_INT, C_INT, Wide) RETURNS CLongLong
+DECLARE P : Pair
+DECLARE U : Vec2
+DECLARE V : Vec2
+DECLARE M : Mixed
+DECLARE F : Vec3f
+DECLARE W : Wide
+P.A <- (C_INT)3
+P.B <- (C_INT)4
+OUTPUT pair_sum(P)
+U.X <- (C_DOUBLE)1.5
+U.Y <- (C_DOUBLE)2
+V.X <- (C_DOUBLE)4
+V.Y <- (C_DOUBLE)0.25
+OUTPUT vec2_dot(U, V)
+M.Tag <- (C_CHAR)'M'
+M.Value <- (C_DOUBLE)2.5
+M.Count <- (C_INT)3
+OUTPUT mixed_score((CShort)-1, M, (C_INT)4)
+F.X <- (CFloat)0.5
+F.Y <- (CFloat)1.25
+F.Z <- (CFloat)2
+OUTPUT vec3f_sum(F)
+W.Lo <- (CLongLong)100
+W.Hi <- (CLongLong)1000
+OUTPUT wide_after_five((C_INT)1, (C_INT)2, (C_INT)3, (C_INT)4, (C_INT)5, W)
-- 
cgit v1.3.1-4-g156e