https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56926
--- Comment #12 from asmwarrior <asmwarrior at gmail dot com> --- Hi, I just did a test on the cygwin 32bit tool chain. 1, download the cygwin installer. 2, install gcc-g++ 4.9.2 and boost 1.57 package 3, run the steps in comment 6, except that you don't need to add the "-ID:\mingw-builds\boost_1_55_0" in the build command, because we can use the boost library installed from the previous step. 4, when building the pch files, I get a 318M pch.h.gch file 5, when building the object file, I get a 365K test.o file So, this bug doesn't happen in the cygwin tool chain, and it looks like the bug only happens in the MinGW and MinGW-W64 tool chain. Any ideas what is the reason of this bug? Maybe, someone can supply a debug version of g++, and let help to run under GDB.