Turn on memory corruption hardening where available#53

Merged

busterb merged 7 commits intolibressl:masterfrom jbarlow83:master

Jan 2, 2015

+251-11

Commits on Dec 23, 2014

configure.ac: Modify clang check to save result to a variable
Jim Barlow
committed
configure.ac: use executable hardening where available
Jim Barlow
committed

Commits on Dec 24, 2014

configure.ac: use executable hardening where available
Jim Barlow
committed

Commits on Dec 30, 2014

Merge recent upstream changes with compiler hardening
Jim Barlow
committed

Commits on Dec 31, 2014

Fix typo causing output of clang test to read "CLANG" instead of yes/no
Jim Barlow
committed
Fix build failure of "make distcheck" (new scripts/ folder missing)
Jim Barlow
committed

Commits on Jan 1, 2015

Change comments to remark on script not being needed for clang >= 5.1
Jim Barlow
committed