mxcl/homebrew — pull request #14351 by samueljohn (2012-08-21 19:07:10+00:00)
Title: Xcode-only: LDFLAGS use -isysroot instead of -L

Turns out that the linker also understands the
-isysroot flag which behaves more natural (in the
sense: "like the internal defaults `/usr/lib` etc.)
than adding `-L$(SDKROOT).
Especially for duplicates, the linker first searches
through all `-L` dirs and then looks at the sysroot
or internal defaults. This is what we want.