[clang] [CUDA] Enable variadic argument support in front-end (PR #161305)

[via cfe-commits]

https://github.com/LuoYuanke created https://github.com/llvm/llvm-project/pull/161305

Variadice argument for NVPTX as been support in
https://github.com/llvm/llvm-project/commit/486d00eca6b6ab470e8324b52cdf9f32023c1c9a
We can enable it in front-end.


>From db658c7032473a291afb5201b70a7f463719bff5 Mon Sep 17 00:00:00 2001
From: Yuanke Luo <ykluo at birentech.com>
Date: Tue, 30 Sep 2025 10:04:46 +0800
Subject: [PATCH] [CUDA] Enable variadic argument support in front-end

Variadice argument for NVPTX as been support in
https://github.com/llvm/llvm-project/commit/486d00eca6b6ab470e8324b52cdf9f32023c1c9a
We can enable it in front-end.
---
 clang/lib/Sema/SemaExpr.cpp   | 5 ++---
 clang/test/SemaCUDA/vararg.cu | 2 +-
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 3b267c1b1693d..2ab14cf0906a7 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -16791,12 +16791,11 @@ ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc,
   Expr *OrigExpr = E;
   bool IsMS = false;
 
-  // CUDA device code does not support varargs.
+  // CUDA device global function does not support varargs.
   if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
     if (const FunctionDecl *F = dyn_cast<FunctionDecl>(CurContext)) {
       CUDAFunctionTarget T = CUDA().IdentifyTarget(F);
-      if (T == CUDAFunctionTarget::Global || T == CUDAFunctionTarget::Device ||
-          T == CUDAFunctionTarget::HostDevice)
+      if (T == CUDAFunctionTarget::Global)
         return ExprError(Diag(E->getBeginLoc(), diag::err_va_arg_in_device));
     }
   }
diff --git a/clang/test/SemaCUDA/vararg.cu b/clang/test/SemaCUDA/vararg.cu
index 34ef367d89820..0238f42dc40a9 100644
--- a/clang/test/SemaCUDA/vararg.cu
+++ b/clang/test/SemaCUDA/vararg.cu
@@ -10,7 +10,7 @@
 #include <stdarg.h>
 #include "Inputs/cuda.h"
 
-__device__ void foo() {
+__global__ void foo() {
   va_list list;
   va_arg(list, int);
 #ifdef EXPECT_VA_ARG_ERR