when building brew, update from llvm 8 to llvm 12
#!/bin/sh -exu
package="$1" ; shift
version="$1" ; shift
-sed -i "" -e '/install-rust/d' -e 's!^ url ".*"$! url "file:///'$(pwd)/../$package-$version'-src.tar.gz"!' \
+sed -i "" -e 's/llvm@8/llvm@12/' -e 's!^ url ".*"$! url "file:///'$(pwd)/../$package-$version'-src.tar.gz"!' \
-e 's!^ sha256 ".*"$! sha256 "'$(shasum -a 256 ../$package-$version-src.tar.gz | awk '{print $1}')'"!' \
Formula/$package.rb
