Hi.
The patch adds new no_stack_protect attribute. The change is requested
from kernel folks and is direct equivalent of Clang's no_stack_protector.
Unlike Clang, I chose to name it no_stack_protect because we already
have stack_protect attribute (used with -fstack-protector-explicit).
First part of the patch contains a small refactoring of an enum, second
implements the functionality.
Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
Ready to be installed?
Thanks,
Martin
0002-Implement-no_stack_protect-attribute.patch
From 6b3e9d32150fe17acb271b7bedee7dc95cad7dc8 Mon Sep 17 00:00:00 2001
From: Martin Liska<mli...@suse.cz>
Date: Fri, 15 May 2020 14:42:12 +0200
Subject: [PATCH 2/2] Implement no_stack_protect attribute.
gcc/ChangeLog:
2020-05-18 Martin Liska<mli...@suse.cz>
PR c/94722
* cfgexpand.c (stack_protect_decl_phase):
Guard with lookup_attribute("no_stack_protect") at
various places.
(expand_used_vars): Likewise here.
* doc/extend.texi: Document no_stack_protect attribute.
gcc/ada/ChangeLog:
2020-05-18 Martin Liska<mli...@suse.cz>
PR c/94722
* gcc-interface/utils.c (handle_no_stack_protect_attribute):
New.
(handle_stack_protect_attribute): Add error message for a
no_stack_protect function.
gcc/c-family/ChangeLog:
2020-05-18 Martin Liska<mli...@suse.cz>
PR c/94722
* c-attribs.c (handle_no_stack_protect_function_attribute): New.
(handle_stack_protect_attribute): Add error message for a
no_stack_protect function.
gcc/testsuite/ChangeLog:
2020-05-18 Martin Liska<mli...@suse.cz>
PR c/94722
* g++.dg/no-stack-protect-attr-2.C: New test.
* g++.dg/no-stack-protect-attr-3.C: New test.
* g++.dg/no-stack-protect-attr.C: New test.
---
gcc/ada/gcc-interface/utils.c | 32 ++++++++
gcc/c-family/c-attribs.c | 33 ++++++++
gcc/cfgexpand.c | 82 ++++++++++---------
gcc/doc/extend.texi | 4 +
.../g++.dg/no-stack-protect-attr-2.C | 7 ++
.../g++.dg/no-stack-protect-attr-3.C | 23 ++++++
gcc/testsuite/g++.dg/no-stack-protect-attr.C | 16 ++++
7 files changed, 158 insertions(+), 39 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/no-stack-protect-attr-2.C
create mode 100644 gcc/testsuite/g++.dg/no-stack-protect-attr-3.C
create mode 100644 gcc/testsuite/g++.dg/no-stack-protect-attr.C
diff --git a/gcc/ada/gcc-interface/utils.c b/gcc/ada/gcc-interface/utils.c
index 1527be4f6d1..144afe37d78 100644
--- a/gcc/ada/gcc-interface/utils.c
+++ b/gcc/ada/gcc-interface/utils.c
@@ -91,6 +91,7 @@ static tree handle_nonnull_attribute (tree *, tree, tree,
int, bool *);
static tree handle_sentinel_attribute (tree *, tree, tree, int, bool *);
static tree handle_noreturn_attribute (tree *, tree, tree, int, bool *);
static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
+static tree handle_no_stack_protect_attribute (tree *, tree, tree, int, bool
*);
static tree handle_noinline_attribute (tree *, tree, tree, int, bool *);
static tree handle_noclone_attribute (tree *, tree, tree, int, bool *);
static tree handle_noicf_attribute (tree *, tree, tree, int, bool *);
@@ -141,6 +142,8 @@ const struct attribute_spec gnat_internal_attribute_table[]
=
handle_noreturn_attribute, NULL },
{ "stack_protect",0, 0, true, false, false, false,
handle_stack_protect_attribute, NULL },
+ { "no_stack_protect",0, 0, true, false, false, false,
+ handle_no_stack_protect_attribute, NULL },
{ "noinline", 0, 0, true, false, false, false,
handle_noinline_attribute, NULL },
{ "noclone", 0, 0, true, false, false, false,
@@ -6523,10 +6526,39 @@ handle_stack_protect_attribute (tree *node, tree name,
tree, int,
warning (OPT_Wattributes, "%qE attribute ignored", name);
*no_add_attrs = true;
}
+ else if (lookup_attribute ("no_stack_protect", DECL_ATTRIBUTES (*node)))
+ {
+ warning (OPT_Wattributes, "%qE attribute ignored due to conflict "
+ "with %qs attribute", name, "no_stack_protect");
+ *no_add_attrs = true;
