How to use AddressSanitizer with GCC?

Question

I'm trying to build my project with

g++ -O0 -g -fsanitize=address -fno-omit-frame-pointer

but get lots of errors like:

/home/user/libs/opencv/include/opencv2/core/mat.hpp:715: undefined reference to `__asan_report_load8'

How to compile project with AddressSanitize support?

My gcc version is 4.8.4.

Answer 1

You need to add -fsanitize=address to compiler flags (both CFLAGS and CXXFLAGS) and linker flags (LDFLAGS). You've probably added it to your compiler flags only.

Note that using explicit -lasan option has been widely discouraged by ASan developers (e.g. here) as it misses some other important linker flags. The only recommended way to link is to use -fsanitize=address.

As a side note, for more aggressive verification flags check Asan FAQ (look for "more aggressive diagnostics").

Answer 2

Make sure you have libasan installed. For example, in Fedora:

dnf install libasan libasan-static

Answer 3

You need to add the switch -lasan -fsanitize=address to your both your compile and link command line to link the correct library.

Note: the original answer -lasan is outdated and should not be used, as per comments