Bumping the compiler version to 6.2.0 breaks 64bit Tor Browser builds
After bumping the GCC version to 6.2.0 due to #13893 (moved) building GCC 6.2.0 is busted for 64bits in our gitian setup:
/usr/bin/ld.bfd.real: gcov.o: relocation R_X86_64_32 against `.rodata' can not be used when making a shared object; recompile with -fPIC