reasonable path to not awful dev setup without system abseil

configure

@@ -121,10 +121,12 @@ if [ -z "${R_S2_ABSL_HOME}" ] && pkg-config absl_base --libs 2>/dev/null; then
   PKG_LIBS="${PKGCONFIG_LIBS} ${PKG_LIBS}"
 else
   # Allow developers to set R_S2_ABSL_HOME in .Renviron to avoid building
-  # Abseil on every package rebuild.
+  # Abseil on every package rebuild. This can be built from this directory using
+  # tools/build_absl.sh path/to/dir (then R_S2_ABSL_HOME=path/to/dir in .Renviron)
   if [ -z "$R_S2_ABSL_HOME" ]; then
     echo "** Building abseil-cpp using cmake"
-    if tools/build_absl.sh; then
+    CMAKE_INSTALL_PREFIX="`pwd`/tools/dist"
+    if tools/build_absl.sh "${CMAKE_INSTALL_PREFIX}"; then
       echo "** Done!"
     else
       echo "** CMake build of Abseil failed"

configure.win

@@ -5,7 +5,8 @@ if pkg-config absl_base --libs 2>/dev/null; then
   echo "Using Abseil from RTools via pkg-config"
 else
   # Build the libraries
-  WIN_CPPFLAGS="-DABSL_FORCE_WAITER_MODE=4" tools/build_absl.sh
+  CMAKE_INSTALL_PREFIX="`pwd`/tools/dist"
+  WIN_CPPFLAGS="-DABSL_FORCE_WAITER_MODE=4" tools/build_absl.sh "${CMAKE_INSTALL_PREFIX}"
 
   # Remove the build directory (its existence causes a check warning on R 4.2)
   rm -rf tools/build

tools/build_absl.sh

@@ -32,8 +32,7 @@ R_CPPFLAGS=`"${R_HOME}/bin/R" CMD config CPPFLAGS`
 R_CXXFLAGS=`"${R_HOME}/bin/R" CMD config CXX17FLAGS`
 LDFLAGS=`"${R_HOME}/bin/R" CMD config LDFLAGS`
 
-CMAKE_INSTALL_PREFIX="`pwd`/tools/dist"
-CMAKE_PREFIX_PATH="`pwd`/tools/dist/lib/cmake:${CMAKE_PREFIX_PATH}"
+CMAKE_INSTALL_PREFIX="$1"
 
 if [ ! -d "tools/build/abseil-cpp" ]; then
     mkdir -p "tools/build/abseil-cpp"
@@ -50,7 +49,6 @@ cd "tools/build/abseil-cpp"
   -DBUILD_SHARED_LIBS=OFF \
   -DCMAKE_POSITION_INDEPENDENT_CODE=ON \
   -DCMAKE_INSTALL_PREFIX="${CMAKE_INSTALL_PREFIX}" \
-  -DCMAKE_PREFIX_PATH="${CMAKE_PREFIX_PATH}" \
   -DCMAKE_OSX_DEPLOYMENT_TARGET=11.3 \
   -DCMAKE_CXX_STANDARD=17 \
   -DABSL_PROPAGATE_CXX_STD=ON \