Rollup of 6 pull requests#71934

Closed

Dylan-DPC-zz wants to merge 23 commits intorust-lang:masterfrom

Dylan-DPC-zz:rollup-71oigdi

Commits on Apr 24, 2020

Commits on May 2, 2020

SipHasher::new() is literally with SipHasher with both keys being 0
hbina
committed

Commits on May 3, 2020

x.py: Give a more helpful error message if curl isn't installed
jyn514
committed

Commits on May 4, 2020

Commits on May 5, 2020

rely on rdlock/wrlock not returning anything but the specified error codes
RalfJung
committed
Rollup merge of #70908 - estebank:suggest-add, r=nikomatsakis
Dylan-DPC
authored
Rollup merge of #71510 - ssomers:btreemap_iter_intertwined, r=Mark-Simulacrum
Dylan-DPC
authored
Rollup merge of #71727 - hbina:simplified_usage, r=Mark-Simulacrum
Dylan-DPC
authored
Rollup merge of #71819 - jyn514:check-for-tools, r=Mark-Simulacrum
Dylan-DPC
authored
Rollup merge of #71889 - RalfJung:rwlock, r=Amanieu
Dylan-DPC
authored
Rollup merge of #71905 - mibac138:x-cmd-alias, r=Mark-Simulacrum
Dylan-DPC
authored