[FS#832] GCC 6.X Toolchain compile error

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - nouman8 (nouman8) 

Attached to Project - LEDE Project
Summary - GCC 6.X Toolchain compile error
Task Type - Bug Report
Category - Toolchain
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Critical
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - /source/build_dir/toolchain-mips_74kc_gcc-6.3.0_musl/gcc-6.3.0/gcc/ubsan.c: In function 'bool ubsan_use_new_style_p(location_t)':
/source/build_dir/toolchain-mips_74kc_gcc-6.3.0_musl/gcc-6.3.0/gcc/ubsan.c:1474:23: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
       || xloc.file == '\0' || xloc.file[0] == '\xff'
                       ^~~~
make[5]: *** [Makefile:1085: ubsan.o] Error 1
make[5]: Leaving directory '/source/build_dir/toolchain-mips_74kc_gcc-6.3.0_musl/gcc-6.3.0-initial/gcc'
make[4]: *** [Makefile:4115: all-gcc] Error 2
make[4]: Leaving directory '/source/build_dir/toolchain-mips_74kc_gcc-6.3.0_musl/gcc-6.3.0-initial'
make[3]: *** [Makefile:37: /source/build_dir/toolchain-mips_74kc_gcc-6.3.0_musl/gcc-6.3.0-initial/.built] Error 2
make[3]: Leaving directory '/source/toolchain/gcc/initial'
make[2]: *** [toolchain/Makefile:98: toolchain/gcc/initial/compile] Error 2
make[2]: Leaving directory '/source'
make[1]: *** [toolchain/Makefile:94: /source/staging_dir/toolchain-mips_74kc_gcc-6.3.0_musl/stamp/.toolchain_compile] Error 2
make[1]: Leaving directory '/source'
make: *** [/source/include/toplevel.mk:208: world] Error 2

Compiling sources with GCC 6.x after the mess explained in #830 and it fails with the error above

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=832