Make px4fmu-v2_default error

i need help ,please.

mj@mj-Lenovo-G470:~/px4/src/Firmware$ make px4fmu-v2_default
– CMAKE_MODULE_PATH: /home/mj/px4/src/Firmware/cmake
– Nuttx build for px4fmu-v2 on m4 hardware, using nsh with ROMFS on px4fmu_common
– Build Type: MinSizeRel
– PX4 VERSION: v1.6.5
– CONFIG: nuttx-px4fmu-v2-default
– The ASM compiler identification is GNU
– Found assembler: /home/mj/gcc-arm-none-eabi-5_4-2016q2/bin/arm-none-eabi-gcc
– Found PythonInterp: /usr/bin/python (found version “2.7.12”)
– Found PY_jinja2: /usr/lib/python2.7/dist-packages/jinja2
CMake Error at CMakeLists.txt:332 (STRING):
string sub-command REGEX, mode MATCH needs at least 5 arguments total to
command.

– C compiler:
CMake Error at CMakeLists.txt:340 (STRING):
string sub-command REGEX, mode MATCH needs at least 5 arguments total to
command.

– C++ compiler:
– Adding ROMFS on px4fmu-v2
– Nuttx build for px4fmu-v2 on m3 hardware, using nsh
– Configuring incomplete, errors occurred!
See also “/home/mj/px4/src/Firmware/build_px4fmu-v2_default/CMakeFiles/CMakeOutput.log”.
/bin/sh: 1: cd: can’t cd to /home/mj/px4/src/Firmware/build_px4fmu-v2_default
Makefile:164: recipe for target ‘px4fmu-v2_default’ failed
make: *** [px4fmu-v2_default] Error 2
mj@mj-Lenovo-G470:~/px4/src/Firmware$

With the current master you should use a never gcc version: GCC 7-2017-q4
Maybe the old version causes that problem.

But i have read a topic in which LorenzMeier said “You have GCC 6 but we’re only supporting versions up to GCC 5 right now. You can install GCC 5 from here: http://dev.px4.io/starting-installing-linux-boutique.html#toolchain-installation80”.So ,are you using the gcc version 2017 ? And dose it work ?

See the updated dev guide. It changed approximately two month ago and now you need the newer GCC version. I am using the one specified in the dev guide and it works for me.

As PX4 is still in development the tool chain can change from time to time.

thank you very much.i appreciate your reply.and it did make a little progress,but still report errors like this:
[ 14%] Built target nuttx_patch_px4fmu-v2
[ 14%] Built target nuttx_configure_px4fmu-v2
[ 14%] Building NuttX for px4fmu-v2 with nsh
make[4]: warning: jobserver unavailable: using -j1. Add ‘+’ to parent make rule.
stdio/lib_sscanf.c: In function ‘vsscanf’:
stdio/lib_sscanf.c:419:28: error: this statement may fall through [-Werror=implicit-fallthrough=]
sign = true;
^
stdio/lib_sscanf.c:420:21: note: here
case ‘u’:
^~~~
cc1: all warnings being treated as errors
make[5]: *** [bin/lib_sscanf.o] Error 1
make[4]: *** [libc/libc.a] Error 2
src/modules/px4iofirmware/CMakeFiles/nuttx_export_px4io-v2.dir/build.make:60: recipe for target ‘px4io-v2/nuttx_export.stamp’ failed
make[3]: *** [px4io-v2/nuttx_export.stamp] Error 2
CMakeFiles/Makefile2:8527: recipe for target ‘src/modules/px4iofirmware/CMakeFiles/nuttx_export_px4io-v2.dir/all’ failed
make[2]: *** [src/modules/px4iofirmware/CMakeFiles/nuttx_export_px4io-v2.dir/all] Error 2
make[2]: *** 正在等待未完成的任务…
stdio/lib_sscanf.c: In function ‘vsscanf’:
stdio/lib_sscanf.c:419:28: error: this statement may fall through [-Werror=implicit-fallthrough=]
sign = true;
^
stdio/lib_sscanf.c:420:21: note: here
case ‘u’:
^~~~
cc1: all warnings being treated as errors
make[5]: *** [bin/lib_sscanf.o] Error 1
make[4]: *** [libc/libc.a] Error 2
CMakeFiles/nuttx_export_px4fmu-v2.dir/build.make:60: recipe for target ‘px4fmu-v2/nuttx_export.stamp’ failed
make[3]: *** [px4fmu-v2/nuttx_export.stamp] Error 2
CMakeFiles/Makefile2:1633: recipe for target ‘CMakeFiles/nuttx_export_px4fmu-v2.dir/all’ failed
make[2]: *** [CMakeFiles/nuttx_export_px4fmu-v2.dir/all] Error 2
Makefile:160: recipe for target ‘all’ failed
make[1]: *** [all] Error 2
Makefile:164: recipe for target ‘px4fmu-v2_default’ failed
make: *** [px4fmu-v2_default] Error 2

I’ve met the question as you too.
Have you worked out any approach to solve the problem?