From d3e81f33994ed85c1887aa751906d85ca5b9c64c Mon Sep 17 00:00:00 2001 From: Ammar Askar Date: Mon, 1 Jun 2020 17:21:43 +0000 Subject: [PATCH] bpo-39943: Fix MSVC warnings in sre extension (GH-20508) (cherry picked from commit 06e3a27a3c863495390a07c695171a8e62a6e0d2) Co-authored-by: Ammar Askar --- Modules/_sre.c | 8 ++++++-- Modules/sre_lib.h | 5 ++++- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/Modules/_sre.c b/Modules/_sre.c index 244e4f1f84dfff..bdc427822d7e10 100644 --- a/Modules/_sre.c +++ b/Modules/_sre.c @@ -454,7 +454,10 @@ state_init(SRE_STATE* state, PatternObject* pattern, PyObject* string, return string; err: - PyMem_Del(state->mark); + /* We add an explicit cast here because MSVC has a bug when + compiling C code where it believes that `const void**` cannot be + safely casted to `void*`, see bpo-39943 for details. */ + PyMem_Del((void*) state->mark); state->mark = NULL; if (state->buffer.buf) PyBuffer_Release(&state->buffer); @@ -468,7 +471,8 @@ state_fini(SRE_STATE* state) PyBuffer_Release(&state->buffer); Py_XDECREF(state->string); data_stack_dealloc(state); - PyMem_Del(state->mark); + /* See above PyMem_Del for why we explicitly cast here. */ + PyMem_Del((void*) state->mark); state->mark = NULL; } diff --git a/Modules/sre_lib.h b/Modules/sre_lib.h index 9cc786321c560a..2657d8d82c6f1c 100644 --- a/Modules/sre_lib.h +++ b/Modules/sre_lib.h @@ -448,12 +448,15 @@ do { \ state->data_stack_base += size; \ } while (0) +/* We add an explicit cast to memcpy here because MSVC has a bug when + compiling C code where it believes that `const void**` cannot be + safely casted to `void*`, see bpo-39943 for details. */ #define DATA_STACK_POP(state, data, size, discard) \ do { \ TRACE(("copy data to %p from %" PY_FORMAT_SIZE_T "d " \ "(%" PY_FORMAT_SIZE_T "d)\n", \ data, state->data_stack_base-size, size)); \ - memcpy(data, state->data_stack+state->data_stack_base-size, size); \ + memcpy((void*) data, state->data_stack+state->data_stack_base-size, size); \ if (discard) \ state->data_stack_base -= size; \ } while (0)