Unusual library path on OS X

Hi Everyone,

I'm building Git 1.20.1 from sources on OS X. Git (and its dependents) were configured with:

  PKGCONFPATH: /usr/local/lib/pkgconfig
       CPPFLAGS: -I/usr/local/include -DNDEBUG
         CFLAGS: -g2 -O2 -march=native -fPIC
       CXXFLAGS: -g2 -O2 -march=native -fPIC
        LDFLAGS: -L/usr/local/lib -Wl,-rpath,/usr/local/lib
         LDLIBS: -ldl -lpthread

For Git it results in a configure called with:

    PERL="$SH_PERL" \
    PKG_CONFIG_PATH="${BUILD_PKGCONFIG[*]}" \
    CPPFLAGS="${BUILD_CPPFLAGS[*]}" \
    CFLAGS="${BUILD_CFLAGS[*]}" \
    CXXFLAGS="${BUILD_CXXFLAGS[*]}" \
    LDFLAGS="${BUILD_LDFLAGS[*]}" \
    LIBS="-lssl -lcrypto -lz ${BUILD_LIBS[*]}" \
./configure --prefix="$BUILD_PREFIX" --with-lib="$BUILD_LIBDIR" \
    ...

BUILD_PREFIX is /usr/local, and BUILD_LIBDIR=/usr/local/lib.

Linking produces the following, which seems a bit unusual. It looks like PREFIX and LIBDIR are being concatenated:

    LINK t/helper/test-fake-ssh
    LINK t/helper/test-line-buffer
    LINK t/helper/test-svn-fe
ld: warning: directory not found for option '-L/usr/local//usr/local/lib'
ld: warning: directory not found for option '-L/usr/local//usr/local/lib'
ld: warning: directory not found for option '-L/usr/local//usr/local/lib'
ld: warning: directory not found for option '-L/usr/local//usr/local/lib'

When I try to use --with-libdir=/usr/local/lib, I get:

    configure: WARNING: unrecognized options: --with-libdir

Jeff