gdb exits when opening variables tree when debuggon linked dll

I have a dll, written in Qt by me. I have a program, written in Qt by me. I connected dll to program in .pro file:
LIBS += -L$$quote(../../shared/mait-01/bin/debug)
#LIBS += -L$$quote(../../shared/mait-01/bin/release)
LIBS += -lmait-011
I want to debug dll code.
When I stoped on breakpoint in dll code and clicked mouse on expand tree elements (see attached image) to see variables and their values, I see error message like QMessageBox style, that GDB terminated unexpectidly.
I have got this errors in QtCreator 2.8.1, downloaded from qtproject as setup. I have it got in QtCreator 2.8.1, builded from sources with mingw32 4.4.0.
I tested that with debuggers: qtcreator-gdb-7.5-mingw32_nt-6.1-i686, qtcreator-gdb-7.4-MINGW32_NT-6.1-i686, gdb-7.5-i686_WinXP, and from old QtSDK 1.2.
I tested it with different programs and dlls, that worked before.

When I downloaded QtCreator 4.6.2 (before upgrade to 4.8.1 I had 4.6.1) this problem disappeared.