From 3ef9d661f45abfaca5d0c0bb2ea9ab60470f1bb7 Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Tue, 25 Oct 2016 11:13:00 +0100 Subject: [PATCH] Don't override operator new if GDB is built with -fsanitize=address Nowadays, if we build GDB with -fsanitize=address, we can get the asan error below, (gdb) quit ================================================================= ==9723==ERROR: AddressSanitizer: alloc-dealloc-mismatch (malloc vs operator delete) on 0x60200003bf70 #0 0x7f88f3837527 in operator delete(void*) (/usr/lib/x86_64-linux-gnu/libasan.so.1+0x55527) #1 0xac8e13 in __gnu_cxx::new_allocator::deallocate(void (**)(), unsigned long) /usr/include/c++/4.9/ext/new_allocator.h:110 #2 0xac8cc2 in __gnu_cxx::__alloc_traits >::deallocate(std::allocator&, void (**)(), unsigned long) /usr/include/c++/4.9/ext/alloc_traits.h:185 .... 0x60200003bf70 is located 0 bytes inside of 8-byte region [0x60200003bf70,0x60200003bf78) allocated by thread T0 here: #0 0x7f88f38367ef in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.1+0x547ef) #1 0xbd2762 in operator new(unsigned long) /home/yao/SourceCode/gnu/gdb/git/gdb/common/new-op.c:42 #2 0xac8edc in __gnu_cxx::new_allocator::allocate(unsigned long, void const*) /usr/include/c++/4.9/ext/new_allocator.h:104 #3 0xac8d81 in __gnu_cxx::__alloc_traits >::allocate(std::allocator&, unsigned long) /usr/include/c++/4.9/ext/alloc_traits.h:182 The reason for this is that we override operator new but don't override operator delete. This patch does the override if the code is NOT compiled with asan. gdb: 2016-10-25 Yao Qi PR gdb/20716 * common/new-op.c (__has_feature): New macro. Don't override operator new if asan is used. --- gdb/ChangeLog | 6 ++++++ gdb/common/new-op.c | 7 +++++++ 2 files changed, 13 insertions(+) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 43175ffcde8..5541086d55c 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2016-10-25 Yao Qi + + PR gdb/20716 + * common/new-op.c (__has_feature): New macro. + Don't override operator new if asan is used. + 2016-10-24 Luis Machado * exec.c (exec_file_locate_attach): Prevent NULL pointer dereference diff --git a/gdb/common/new-op.c b/gdb/common/new-op.c index 5ba4d6e9ca6..f04c5cbbfc0 100644 --- a/gdb/common/new-op.c +++ b/gdb/common/new-op.c @@ -17,6 +17,12 @@ You should have received a copy of the GNU General Public License along with this program. If not, see . */ +/* GCC does not understand __has_feature. */ +#if !defined(__has_feature) +# define __has_feature(x) 0 +#endif + +#if !__has_feature(address_sanitizer) && !defined(__SANITIZE_ADDRESS__) #include "common-defs.h" #include "host-defs.h" #include @@ -83,3 +89,4 @@ operator new[] (std::size_t sz, const std::nothrow_t&) { return ::operator new (sz, std::nothrow); } +#endif