Hi, I'm trying to develop an app using the vcl library. Unfortunately, I cannot start the app with gdb when preloading the library. I start it with this command: > > sudo VCL_DEBUG=2 LDP_DEBUG=2 > LD_PRELOAD=/home/hardcore/ductm/vpp/lib64/libvcl_ldpreload.so gdb > ./epoll-server
Sometimes, gdb crashes at the beginning due to buffer overflow. Here is the bt: > > *** buffer overflow detected ***: gdb terminated > ======= Backtrace: ========= > /lib64/libc.so.6(__fortify_fail+0x37)[0x7f2473240cb7] > /lib64/libc.so.6(+0x10be80)[0x7f247323ee80] > /lib64/libc.so.6(+0x10dc27)[0x7f2473240c27] > gdb[0x5d6178] > gdb(add_file_handler+0x36)[0x5d70d6] > gdb[0x4be307] > gdb(_initialize_python+0x37b)[0x51de4b] > gdb(gdb_init+0x2f)[0x6907af] > gdb[0x5d073f] > gdb(catch_errors+0x8a)[0x5ce68a] > gdb(gdb_main+0x24)[0x5d1784] > gdb(main+0x3e)[0x45734e] > /lib64/libc.so.6(__libc_start_main+0xf5)[0x7f2473154af5] > gdb[0x457391] Sometimes, gdb can start but when I try to run any app, it just hangs up. When printing some logs, I realize that the ldp app is created 2 times. At the second one, it hangs when trying to connect to vpp: > > > > > (gdb) run -p 12345 > > > > Starting program: /home/hardcore/ductm/./epoll-server -p 12345 > > > > vppcom_app_create:2330: VCL<18422>: configured VCL debug level (2) from > VCL_DEBUG! > > > > vppcom_cfg_heapsize:1819: VCL<18422>: using default heapsize 268435456 > (0x10000000) > > > > vppcom_cfg_heapsize:1965: VCL<18422>: allocated VCL heap = 0x7fffe25a7000, > size 268435456 (0x10000000) > > > > vppcom_cfg_read:1985: VCL<18422>: using default configuration. > > > > vppcom_connect_to_vpp:707: VCL<18422>: app (ldp-18422-app) connecting to > VPP api (/vpe-api)... > > > > vppcom_connect_to_vpp:723: VCL<18422>: app (ldp-18422-app) is connected to > VPP! > > > > vppcom_app_create:2461: VCL<18422>: sending session enable > > > > vppcom_app_create:2472: VCL<18422>: sending app attach > > > > vppcom_app_create:2485: VCL<18422>: app_name 'ldp-18422-app', > my_client_index 768 (0x300) > > > > ldp_init:150: LDP<18422>: configured LDP debug level (2) from the env var > LDP_DEBUG! > > > > ldp_init:218: LDP<18422>: LDP initialization: done! > > > > ldp_constructor:3456: LDP<18422>: LDP constructor: done! > > > > > > > > [Thread debugging using libthread_db enabled] > > > > Using host libthread_db library "/lib64/libthread_db.so.1". > > > > > > > > vppcom_app_create:2330: VCL<18422>: configured VCL debug level (2) from > VCL_DEBUG! > > > > vppcom_cfg_heapsize:1819: VCL<18422>: using default heapsize 268435456 > (0x10000000) > > > > vppcom_cfg_heapsize:1965: VCL<18422>: allocated VCL heap = 0x7fffe27d1000, > size 268435456 (0x10000000) > > > > vppcom_cfg_read:1985: VCL<18422>: using default configuration. > > > > vppcom_connect_to_vpp:707: VCL<18422>: app (ldp-18422-app) connecting to > VPP api (/vpe-api)... > > Running the app without gdb works for some apps; some others show unexpected behaviors. I use the VCL lib from master branch (18.07) Does this lib require some specific ways to work with gdb? Thank you!
