Disable zlib

Author: tadeja

cpp/cmake_modules/ThirdpartyToolchain.cmake

@@ -2073,7 +2073,10 @@ function(build_protobuf)
         "-DCMAKE_C_FLAGS="
         "-DCMAKE_INSTALL_PREFIX=${PROTOBUF_HOST_PREFIX}"
         -Dprotobuf_BUILD_TESTS=OFF
-        -Dprotobuf_DEBUG_POSTFIX=)
+        -Dprotobuf_DEBUG_POSTFIX=
+        # OFF so protobuf does not take conda's zlib and add its include dir
+        # globally, so vendored Abseil sources compile against env's old headers
+        -Dprotobuf_WITH_ZLIB=OFF)
     if(ABSL_VENDORED)
       # Force protobuf to reuse Arrow's already-extracted absl source
       # so we don't re-download and we don't have issues with multiple abseil.