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| author | Longjun Luo <luolongjuna@gmail.com> | 2023-04-30 12:28:06 -0600 |
|---|---|---|
| committer | Jeff Law <jlaw@ventanamicro> | 2023-04-30 12:28:06 -0600 |
| commit | e7ce7c4905fd254760b1cd187752a03bc0c148ba (patch) | |
| tree | cb515cfd3af5bd61643d4680781bcd6d25948c3e /libcpp/init.cc | |
| parent | 2744dbb9ecf104a113da3a0f39115da4653bb676 (diff) | |
| download | gcc-e7ce7c4905fd254760b1cd187752a03bc0c148ba.zip gcc-e7ce7c4905fd254760b1cd187752a03bc0c148ba.tar.gz gcc-e7ce7c4905fd254760b1cd187752a03bc0c148ba.tar.bz2 | |
[PATCH] libcpp: suppress builtin macro redefined warnings for __LINE__
From 0821df518b264e754d698d399f98be1a62945e32 Mon Sep 17 00:00:00 2001
From: Longjun Luo <luolongjuna@gmail.com>
Date: Thu, 12 Jan 2023 23:59:54 +0800
Subject: [PATCH] libcpp: suppress builtin macro redefined warnings for
__LINE__
As implied in
gcc.gnu.org/legacy-ml/gcc-patches/2008-09/msg00076.html,
gcc provides -Wno-builtin-macro-redefined to suppress warning when
redefining builtin macro. However, at that time, there was no
scenario for __LINE__ macro.
But, when we try to build a live-patch, we compare sections by using
-ffunction-sections. Some same functions are considered changed because
of __LINE__ macro.
At present, to detect such a changed caused by __LINE__ macro, we
have to analyse code and maintain a function list. For example,
in kpatch, check this commit
github.com/dynup/kpatch/commit/0e1b95edeafa36edb7bcf11da6d1c00f76d7e03d.
So, in this scenario, when we try to compared sections, it would
be better to support suppress builtin macro redefined warnings for
__LINE__ macro.
libcpp:
* init.cc (builtin_array): Do not always warn for a redefinition
of __LINE__.
gcc/testsuite
* gcc.dg/builtin-redefine.c: Test for redefintion warnings
for __LINE__.
* gcc.dg/builtin-redefine-1.c: New test.
Diffstat (limited to 'libcpp/init.cc')
| -rw-r--r-- | libcpp/init.cc | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/libcpp/init.cc b/libcpp/init.cc index c508f06..bdeccff 100644 --- a/libcpp/init.cc +++ b/libcpp/init.cc @@ -421,7 +421,7 @@ static const struct builtin_macro builtin_array[] = B("__FILE__", BT_FILE, false), B("__FILE_NAME__", BT_FILE_NAME, false), B("__BASE_FILE__", BT_BASE_FILE, false), - B("__LINE__", BT_SPECLINE, true), + B("__LINE__", BT_SPECLINE, false), B("__INCLUDE_LEVEL__", BT_INCLUDE_LEVEL, true), B("__COUNTER__", BT_COUNTER, true), /* Make sure to update the list of built-in |