Setting OPENBLAS_TARGET_ARCH should disable OPENBLAS_DYNAMIC_ARCH by default
In \, only estimate rank and use complete orthogonal factorization for pivoted qr factorizations.
Merge pull request #8860 from JuliaLang/sf/openblas_dynamic_arch

Setting OPENBLAS_TARGET_ARCH disables OPENBLAS_DYNAMIC_ARCH by default
Small integer powers are no longer slow.

This has been fixed in issue #2741.
Merge pull request #8878 from ntessore/nt/doc-perf

Updated manual: Small integer powers are no longer slow.
Adapt to LLVM3.6 API change
Mention update to machinefile in `NEWS`.
Merge pull request #8888 from wavexx/machinecount_news

Mention update to machinefile in `NEWS`.
Define eltype for Factorizations
rename String => AbstractString
Bytes: one approach to a jl_bytes_t type.
Bytes: a new approach with less built-in stuff.
wip: more functionality for the Bytes type
wip: Str (Bytes-based string type)
Bytes: enable GC marking of Bytes objects.
Bytes: make bytesref a builtin (prep for adding it to codegen).
wip: take a crack at native getindex(::Bytes, ::Int); no dice.

This was the best I could come up with but the code is too complex
for LLVM to figure out what I'm trying to do and do it efficiently.
It seems like we really may need to provide custom code gen.