[clang] [clang][bytecode] Disable tail calls on MSVC (PR #188033)

[Timm Baeder via cfe-commits]

https://github.com/tbaederr created https://github.com/llvm/llvm-project/pull/188033

Since I now have to wait for CI to do a revert, might as well to the actual change first.

>From ab29e63de328c7aee47c197a1c9190829e63a74b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbaeder at redhat.com>
Date: Mon, 23 Mar 2026 14:05:29 +0100
Subject: [PATCH] [clang][bytecode] Disable tail calls on MSVC

---
 clang/lib/AST/ByteCode/Interp.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index 6e7a60d5e4332..abe7b31082302 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -37,7 +37,9 @@ using namespace clang::interp;
 #endif
 
 // On MSVC, musttail does not guarantee tail calls in debug mode.
-#if (defined(_MSC_VER) && defined(_DEBUG)) || !defined(MUSTTAIL)
+// We disable it on MSVC generally since it doesn't seem to be able
+// to handle the way we use tailcalls.
+#if defined(_MSC_VER) || !defined(MUSTTAIL)
 #define MUSTTAIL
 #define USE_TAILCALLS 0
 #else