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authorGuillaume Gomez <guillaume1.gomez@gmail.com>2025-07-21 14:34:12 +0200
committerGuillaume Gomez <guillaume1.gomez@gmail.com>2025-07-22 14:28:48 +0200
commita27f3e3fd1e4d16160f8885b6b06665b5319f56c (patch)
treeb033935392cbadf6f85d2dbddf433a88e323aeeb /tests/codegen-llvm/cffi/c-variadic-opt.rs
parented93c1783b404d728d4809973a0550eb33cd293f (diff)
downloadrust-a27f3e3fd1e4d16160f8885b6b06665b5319f56c.tar.gz
rust-a27f3e3fd1e4d16160f8885b6b06665b5319f56c.zip
Rename `tests/codegen` into `tests/codegen-llvm`
Diffstat (limited to 'tests/codegen-llvm/cffi/c-variadic-opt.rs')
-rw-r--r--tests/codegen-llvm/cffi/c-variadic-opt.rs30
1 files changed, 30 insertions, 0 deletions
diff --git a/tests/codegen-llvm/cffi/c-variadic-opt.rs b/tests/codegen-llvm/cffi/c-variadic-opt.rs
new file mode 100644
index 00000000000..7e544ee7f37
--- /dev/null
+++ b/tests/codegen-llvm/cffi/c-variadic-opt.rs
@@ -0,0 +1,30 @@
+//@ compile-flags: -C opt-level=3
+
+#![crate_type = "lib"]
+#![feature(c_variadic)]
+#![no_std]
+use core::ffi::VaList;
+
+extern "C" {
+    fn vprintf(fmt: *const i8, ap: VaList) -> i32;
+}
+
+// Ensure that `va_start` and `va_end` are properly injected even
+// when the "spoofed" `VaListImpl` is not used.
+#[no_mangle]
+pub unsafe extern "C" fn c_variadic_no_use(fmt: *const i8, mut ap: ...) -> i32 {
+    // CHECK: call void @llvm.va_start
+    vprintf(fmt, ap.as_va_list())
+    // CHECK: call void @llvm.va_end
+}
+
+// Check that `VaListImpl::clone` gets inlined into a direct call to `llvm.va_copy`
+#[no_mangle]
+pub unsafe extern "C" fn c_variadic_clone(fmt: *const i8, mut ap: ...) -> i32 {
+    // CHECK: call void @llvm.va_start
+    let mut ap2 = ap.clone();
+    // CHECK: call void @llvm.va_copy
+    let res = vprintf(fmt, ap2.as_va_list());
+    res
+    // CHECK: call void @llvm.va_end
+}