We currently use a 32-bit Rust toolchain for win32 builds, but this can lead
to OOM situations. This patch makes win32 builds use a 64-bit Rust toolchain,
which requires a little bit of extra configuration because rustc needs to
be able to find a link.exe that produces 64-bit binaries for building
things like build scripts, which are host binaries.
We will now generate a batch file that sets LIB to the paths to 64-bit
libraries and invokes the x64-targeting link.exe, and add a section to the
.cargo/config file to instruct cargo to use that batch file as the linker
when producing 64-bit binaries.
MozReview-Commit-ID: 9vKBbm7Gvra
--HG--
extra : rebase_source : 599b3b661c7a8a5db1f32a2a9732fc202fb55e1e
Ted Mielczarek