transpile: add generics test

Author: ahomescu

c2rust-transpile/tests/snapshots.rs

@@ -374,6 +374,11 @@ fn test_fn_attrs() {
     transpile("fn_attrs.c").run();
 }
 
+#[test]
+fn test_generics() {
+    transpile("generics.c").run();
+}
+
 #[test]
 fn test_gotos() {
     transpile("gotos.c").run();

c2rust-transpile/tests/snapshots/generics.c

@@ -0,0 +1,35 @@
+#define inc(x) (_Generic((x), \
+    float: (x) + 1.0f,        \
+    double: (x) + 1.0,        \
+    default: (x) + 1))
+
+struct s { int x; };
+struct t { int y; };
+#define cast(p) (_Generic((p), \
+    const struct s *: (const struct t *)(p), \
+    struct s *:       (struct t *)(p)))
+
+#define unqual_typeof(x) typeof(_Generic((x), \
+    int: (int)0, const int: (int)0, default: (x)))
+
+void foo() {
+    int x = inc(42);
+    double y = inc(42.0);
+    float z = inc(42.0f);
+
+    int n = 0;
+    _Generic((n++), int: n, default: n);  // n must end up 0, not 1
+
+    // No default
+    int m = 0;
+    n = _Generic((m), int: m);
+
+    struct s s;
+    struct s *p1 = &s;
+    const struct s *p2 = &s;
+    struct t *t1 = cast(p1);
+    const struct t *t2 = cast(p2);
+
+    const int cx = n;
+    unqual_typeof(x) ut_y = cx;
+}

c2rust-transpile/tests/snapshots/snapshots__transpile@generics.c.2021.clang15.snap

@@ -0,0 +1,40 @@
+---
+source: c2rust-transpile/tests/snapshots.rs
+expression: cat tests/snapshots/generics.2021.clang15.rs
+---
+#![allow(
+    clippy::missing_safety_doc,
+    dead_code,
+    non_camel_case_types,
+    non_snake_case,
+    non_upper_case_globals,
+    unused_assignments,
+    unused_mut
+)]
+#![feature(raw_ref_op)]
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct s {
+    pub x: ::core::ffi::c_int,
+}
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct t {
+    pub y: ::core::ffi::c_int,
+}
+#[no_mangle]
+pub unsafe extern "C" fn foo() {
+    let mut x: ::core::ffi::c_int = 42 as ::core::ffi::c_int + 1 as ::core::ffi::c_int;
+    let mut y: ::core::ffi::c_double = 42.0f64 + 1.0f64;
+    let mut z: ::core::ffi::c_float = 42.0f32 + 1.0f32;
+    let mut n: ::core::ffi::c_int = 0 as ::core::ffi::c_int;
+    let mut m: ::core::ffi::c_int = 0 as ::core::ffi::c_int;
+    n = m;
+    let mut s: s = s { x: 0 };
+    let mut p1: *mut s = &raw mut s;
+    let mut p2: *const s = &raw mut s;
+    let mut t1: *mut t = p1 as *mut t;
+    let mut t2: *const t = p2 as *const t;
+    let cx: ::core::ffi::c_int = n;
+    let mut ut_y: ::core::ffi::c_int = cx as ::core::ffi::c_int;
+}

c2rust-transpile/tests/snapshots/snapshots__transpile@generics.c.2024.clang15.snap

@@ -0,0 +1,40 @@
+---
+source: c2rust-transpile/tests/snapshots.rs
+expression: cat tests/snapshots/generics.2024.clang15.rs
+---
+#![allow(
+    clippy::missing_safety_doc,
+    dead_code,
+    non_camel_case_types,
+    non_snake_case,
+    non_upper_case_globals,
+    unsafe_op_in_unsafe_fn,
+    unused_assignments,
+    unused_mut
+)]
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct s {
+    pub x: ::core::ffi::c_int,
+}
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct t {
+    pub y: ::core::ffi::c_int,
+}
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn foo() {
+    let mut x: ::core::ffi::c_int = 42 as ::core::ffi::c_int + 1 as ::core::ffi::c_int;
+    let mut y: ::core::ffi::c_double = 42.0f64 + 1.0f64;
+    let mut z: ::core::ffi::c_float = 42.0f32 + 1.0f32;
+    let mut n: ::core::ffi::c_int = 0 as ::core::ffi::c_int;
+    let mut m: ::core::ffi::c_int = 0 as ::core::ffi::c_int;
+    n = m;
+    let mut s: s = s { x: 0 };
+    let mut p1: *mut s = &raw mut s;
+    let mut p2: *const s = &raw mut s;
+    let mut t1: *mut t = p1 as *mut t;
+    let mut t2: *const t = p2 as *const t;
+    let cx: ::core::ffi::c_int = n;
+    let mut ut_y: ::core::ffi::c_int = cx as ::core::ffi::c_int;
+}