I using the PJSIP With MinGW (MSYS2) -- The C compiler identification is GNU 7.3.0 -- The CXX compiler identification is GNU 7.3.0 I using the last version from trunk svn and try configure with ./configure --disable-video --disable-speex-aec --disable-l16-codec --disable-speex-codec --disable-sdl --disable-openh264 --disable-v4l2 --disable-opus --disable-opencore-amr --disable-ssl --disable-libyuv --disable-libwebrtc --disable-bcg729 --disable-sound --disable-resample --disable-shared I try change the value from PJ_IOQUEUE_MAX_HANDLES AND __FD_SETSIZE but i receive the same error. Below is my config_site.h ----------------------------------------------------------------------------------------------------------- // Uncomment to get minimum footprint (suitable for 1-2 concurrent calls only) #define PJ_CONFIG_MINIMAL_SIZE #undef PJ_OS_HAS_CHECK_STACK /* Putting max handles to lower than 32 will make pj_fd_set_t size smaller * than native fdset_t and will trigger assertion on sock_select.c. */ #define PJ_FD_SETSIZE_SETABLE 1 #undef PJ_IOQUEUE_MAX_HANDLES #define PJ_IOQUEUE_MAX_HANDLES 32 #define __FD_SETSIZE 32 #define PJ_CRC32_HAS_TABLES 0 #define PJSIP_MAX_TSX_COUNT 15 #define PJSIP_MAX_DIALOG_COUNT 15 #define PJSIP_UDP_SO_SNDBUF_SIZE 4000 #define PJSIP_UDP_SO_RCVBUF_SIZE 4000 #define PJMEDIA_HAS_ALAW_ULAW_TABLE 0 #define PJ_OS_HAS_CHECK_STACK 0 #define PJ_LOG_MAX_LEVEL 0 #define PJ_ENABLE_EXTRA_CHECK 0 #define PJ_HAS_ERROR_STRING 0 // Uncomment to get maximum performance //#define PJ_CONFIG_MAXIMUM_SPEED // #define FD_SETSIZE_SETABLE 1 #define PJMEDIA_HAS_ILBC_CODEC 1 #define PJMEDIA_HAS_GSM_CODEC 1 #define PJMEDIA_HAS_G711_CODEC 1 #define PJMEDIA_HAS_GSM_CODEC 1 #define PJMEDIA_HAS_INTEL_IPP 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_G729 0 #define PJMEDIA_HAS_VIDEO 0 #define PJMEDIA_HAS_SRTP 0 #define PJMEDIA_HAS_G722_CODEC 0 #define PJMEDIA_HAS_SPEEX_CODEC 0 #define PJMEDIA_HAS_OPUS_CODEC 0 #define PJMEDIA_HAS_L16_CODEC 0 #define PJMEDIA_HAS_G722_CODEC 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_AMR 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_AMRWB 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_G723_1 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_G726 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_G728 0 #define PJMEDIA_HAS_INTEL_IPP_CODEC_G722_1 0 #define PJSIP_REGISTER_CLIENT_CHECK_CONTACT 0