d34d77a build: verify that the assembler can handle crc32 functions (Cory Fields)
Pull request description:
Also, enable crc32 even if -msse4.2 wasn't added by us, as long as it works. This allows custom flags (such as -march=native) to work as expected.
Addresses #10670.
Tree-SHA512: e1a41a87b078d270bc645814315b229ad9c16556a4d14fb66b27a65b28d0caf9bf324f8c1e221854992aa17f53466eece06faebbf74d59b3d4ff2e6db6c614a4
0c4e6ce Add MIT license to build-aux/m4 scripts (Luke Dashjr)
3f8a5d8 Trivial: build-aux/m4/l_atomic: Fix typo (Luke Dashjr)
3b4b6dc Add MIT license to autogen.sh and share/genbuild.sh (Luke Dashjr)
f4dffdd Add MIT license to Makefiles (Luke Dashjr)
This is a cherry-pick of a4625acb with minor conflict
resolution.
Conflicts:
src/Makefile.am
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leveldb: integrate leveldb into our buildsystem
leveldb's buildsystem causes us a few problems:
- breaks out-of-tree builds
- forces flags used for some tools
- limits cross builds
Rather than continuing to add wrappers around it, simply integrate it into our
build.