Fix Boost 1.58.0 build for mips arch #6937

The Boost 1.58 can't support build for MIPS32 on a x86_64 machine, the error message is" unrecognized command line option '-m32'". The Boost.Build for version 1.58.0 requires a patch for gcc.jam. This patch prevents bjam from adding -m32 and -m64 options to gcc compiler, when compiling for targets that use the mips1 arch.

Bug discussed here: https://github.com/openwrt/packages/issues/1160

utACK

Though something is clearly going wrong in boost cross-compilation,

• the host platform should not influence in any way what gets passed to the target compiler
• according to man gcc, m32/m64 is only supported on "i386 and x86-64" so I think it would make sense to make the condition the other way around instead of a platform blacklist when not to pass it

Arguably an upstream issue and it does make sense to include a workaround patch temporarily...

Looks like this has been fixed upstream in https://github.com/boostorg/build/commit/cbddcde5953c8e51f52bfe612f53d0b779ade5f3

Thanks @fanquake . Seems what they did is:

-            if $(arch) != arm
+            if $(arch) = power || $(arch) = sparc || $(arch) = x86

Which is better as it explicitly defines which platforms can use -mXX (didn't know about power and sparc).

An alternative would be to bump boost to 1.59 (which includes this). Seems to work fine in local testing.

@theuni What do you think is best here?

@laanwj Agree with a bump to 1.59.

Closing in favor of #6980