lazier config

configure

@@ -108,13 +108,19 @@ else
 fi
 
 # For now, just build static abseil-cpp using cmake
-tools/build_absl.sh
+ABSL_HOME=`pwd`/tools/dist
+if [ -d "${ABSL_HOME}" ]; then
+  echo "Using pre-built abseil-cpp at ${ABSL_HOME}"
+else
+  tools/build_absl.sh
+fi
+
 
 # Unfortunately tracing the dependencies here is difficult but the following
 # list is required (depsite s2 directly requiring little of this)
 ABSL_LIBS="-labsl_base -labsl_city -labsl_cord -labsl_cord_internal -labsl_cordz_functions -labsl_cordz_handle -labsl_cordz_info -labsl_hash -labsl_hashtablez_sampler -labsl_int128 -labsl_kernel_timeout_internal -labsl_low_level_hash -labsl_malloc_internal -labsl_raw_hash_set -labsl_raw_logging_internal -labsl_spinlock_wait -labsl_stacktrace -labsl_str_format_internal -labsl_strerror -labsl_string_view -labsl_strings -labsl_strings_internal -labsl_synchronization -labsl_throw_delegate -labsl_time -labsl_time_zone"
-PKG_CFLAGS="-I`pwd`/tools/dist/include ${PKG_CFLAGS}"
-PKG_LIBS="-L`pwd`/tools/dist/lib ${ABSL_LIBS} ${PKG_LIBS}"
+PKG_CFLAGS="-I${ABSL_HOME}/include ${PKG_CFLAGS}"
+PKG_LIBS="-L${ABSL_HOME}/lib ${ABSL_LIBS} ${PKG_LIBS}"
 
 # From apache/arrow/r/configure:
 # If on Raspberry Pi, need to manually link against latomic