Use which C compiler? [gcc --sysroot=/usr/gcc-4.9.2/sysroot]
/usr/gcc-4.9.2/bin/ld: warning: libm.so, needed by /usr/gcc-4.9.2/sysroot/usr/lib/libperl.so, not found (try using -rpath or -rpath-link)
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `log'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `sqrt'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `ceil'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `floor'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `scalbnl'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `modf'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `fmod'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `cos'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `sin'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `atan2'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `pow'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `exp'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `ilogbl'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `frexp'
collect2: error: ld returned 1 exit status
Uh-oh, the C compiler 'gcc --sysroot=/usr/gcc-4.9.2/sysroot' doesn't seem to be working.
/usr/gcc-4.9.2/bin/ld: warning: libm.so, needed by /usr/gcc-4.9.2/sysroot/usr/lib/libperl.so, not found (try using -rpath or -rpath-link)
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `log'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `sqrt'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `ceil'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `floor'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `scalbnl'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `modf'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `fmod'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `cos'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `sin'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `atan2'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `pow'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `exp'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `ilogbl'
/usr/gcc-4.9.2/sysroot/usr/lib/libperl.so: undefined reference to `frexp'
collect2: error: ld returned 1 exit status
Uh-oh, the C compiler 'gcc --sysroot=/usr/gcc-4.9.2/sysroot' doesn't seem to be working.
You need to find a working C compiler.
Either (purchase and) install the C compiler supplied by your OS vendor,
or for a free C compiler try http://gcc.gnu.org/
I cannot continue any further, aborting.