Re: [PATCH v2] tcg: Silence ubsan error on tcg_splitwx_diff causing overflow

[Richard Henderson]

On 6/5/26 06:25, Fabiano Rosas wrote:

UBSAN complains:
runtime error: addition of unsigned offset to 0x7bc06e1f5000
overflowed to 0x7bc02e1f5000

Change tcg_splitwx_diff to ptrdiff_t and silence the error.

Signed-off-by: Fabiano Rosas <faro...@suse.de>
---
  include/tcg/tcg.h | 2 +-
  tcg/tcg.c         | 2 +-
  2 files changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Richard Henderson <richard.hender...@linaro.org>


r~

diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h
index 45c7e118c3..7669dc1c2d 100644
--- a/include/tcg/tcg.h
+++ b/include/tcg/tcg.h
@@ -447,7 +447,7 @@ static inline bool temp_readonly(TCGTemp *ts)

extern __thread TCGContext *tcg_ctx;

  extern const void *tcg_code_gen_epilogue;
-extern uintptr_t tcg_splitwx_diff;
+extern ptrdiff_t tcg_splitwx_diff;
  extern TCGv_env tcg_env;

bool in_code_gen_buffer(const void *p);

diff --git a/tcg/tcg.c b/tcg/tcg.c
index 2ca44766f6..1e77f2365a 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -244,7 +244,7 @@ unsigned int tcg_cur_ctxs;
  unsigned int tcg_max_ctxs;
  TCGv_env tcg_env;
  const void *tcg_code_gen_epilogue;
-uintptr_t tcg_splitwx_diff;
+ptrdiff_t tcg_splitwx_diff;

#ifndef CONFIG_TCG_INTERPRETER

  tcg_prologue_fn *tcg_qemu_tb_exec;