https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89298
--- Comment #3 from Keerecles <lee_shao at 126 dot com> --- (In reply to Jakub Jelinek from comment #2) > It is not clear how that can compile, because both > unsigned int g_var =0; > and > extern unsigned int g_var =0; > are g_var definitions, so if that is in multiple TUs, linker should fail to > link that. No multiple definitions and the program is successfully compiled and linked. > In the other snippet you mention > int g_var_a; > which is something very different (unless -fno-common), that is a common var > and ASAN doesn't instrument those. Sorry, I made a mistake. In my application, ASAN reports global-buffer-overflow just on the global g_var. "int g_var_a;" should be "int g_var;" Here is the ASAN log : $ LD_PRELOAD=/usr/local/gcc-8.1/lib/libasan.so gdb ./App $ b ***/***/AAA.c:288 $ run $ Breakpoint 1 288 g_var=1; $ p &g_var $ $1 = (int) 0xe04e4620 <g_var> $ n $ ==106196==ERROR: AddressSanitizer: global-buffer-overflow on address 0x08d09bc0 at pc 0xde57b983 bp 0xffffcfe8 sp 0xffffcfdc [Here the address (0x08d09bc0) is not 0xe04e4620 ] $ #0 0xde57b982 in ***/***/AAA.c:288 $ 0x08d09bc0 is located 0 bytes to the right of global variable 'g_var_others' defined in *** $ 0x08d09bc0 is located 0 bytes inside of global variable 'g_var' defined in ***
