variable tracking size limit exceeded warning on Debian Jessie #10030

While compiling in the Docker with debian:latest, updated, gcc version 4.9.2 (Debian 4.9.2-10), I have seen this:

In file included from /usr/include/boost/test/unit_test.hpp:20:0,
                 from test/script_tests.cpp:28:
test/script_tests.cpp: In member function 'void script_tests::script_build::test_method()':
test/script_tests.cpp:473:22: note: variable tracking size limit exceeded with -fvar-tracking-assignments, retrying without
 BOOST_AUTO_TEST_CASE(script_build)
                      ^

I have seen this warning for the first time. No other system I compile on show this.

According to stack overflow:

This is just a note from the compiler that the debug info for the particular function will have lower quality, because your code of function is too large/complex so variable tracking reached limit of hash table slots.

Seems unimportant, so closing this.