ASAN AddressSanitizer complains on memory leak - c++

Question

I'm using ASAN address sanitizer to detect memory issues. When the program stops ASAN complains about the following:
==102121==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 537 byte(s) in 1 object(s) allocated from:
#0 0x75cb48 in operator new(unsigned long) (/home/app+0x75cb48)
#1 0x7dca83 in __gnu_cxx::new_allocator<char>::allocate(unsigned long, void const*) /opt/rh/devtoolset-7/root/usr/include/c++/7/ext/new_allocator.h:111
#2 0x7ce766 in std::string::_Rep::_S_create(unsigned long, unsigned long, std::allocator<char> const&) /opt/rh/devtoolset-7/root/usr/include/c++/7/bits/basic_string.tcc:1057
#3 0x7cc54d in std::string::_Rep::_M_clone(std::allocator<char> const&, unsigned long) (/home/app+0x7cc54d)
#4 0x7c1f2a in std::string::reserve(unsigned long) /opt/rh/devtoolset-7/root/usr/include/c++/7/bits/basic_string.tcc:960
#5 0x7fa0a639c6f5 in std::basic_stringbuf<char, std::char_traits<char>, std::allocator<char> >::overflow(int) (/lib64/libstdc++.so.6+0x9b6f5)
Direct leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x75cec8 in operator new(unsigned long, std::nothrow_t const&) (/home/app+0x75cec8)
#1 0x7fa0a635df1d in __cxa_thread_atexit (/lib64/libstdc++.so.6+0x5cf1d)
Indirect leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x75cec8 in operator new(unsigned long, std::nothrow_t const&) (/home/app+0x75cec8)
#1 0x7fa0a635df1d in __cxa_thread_atexit (/lib64/libstdc++.so.6+0x5cf1d)
I've seen on the ASAN page that it can come from the fact the the standard library is statically linked. Although, in my case it is dynamic one.
The application is compiled with devtoolset-7 on RHEL.
Do you have any idea where the leak comes from?

Answer 1

You can get more info than
#0 0x75cb48 in operator new(unsigned long) (/home/app+0x75cb48)
by using llvm-symbolizer.
Download it, and set the environment variable
ASAN_SYMBOLIZER_PATH=/usr/where/ever/the/binary/is
If you are sure that the leak is a false alarm, you can use a suppression file:
create a suppression text file and add to it: leak: __cxa_thread_atexit
Set environment variable
LSAN_OPTIONS=suppressions=path/to/suppr.txt
and then run your app.
http://clang.llvm.org/docs/AddressSanitizer.html#symbolizing-the-reports