diff --git a/builds/cmake/CMakeLists.txt b/builds/cmake/CMakeLists.txt
index d71106a0..3032b5a4 100644
--- a/builds/cmake/CMakeLists.txt
+++ b/builds/cmake/CMakeLists.txt
@@ -45,7 +45,7 @@ set( CMAKE_CXX_STANDARD_REQUIRED ON )
 # Warn on all stuff.
 check_cxx_compiler_flag( "-Wall" HAS_FLAG_WALL )
 if ( HAS_FLAG_WALL )
-    add_compile_options( "-Wall" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wall> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wall" )
 endif()
@@ -53,7 +53,7 @@ endif()
 # Warn on extra stuff.
 check_cxx_compiler_flag( "-Wextra" HAS_FLAG_WEXTRA )
 if ( HAS_FLAG_WEXTRA )
-    add_compile_options( "-Wextra" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wextra> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wextra" )
 endif()
@@ -61,7 +61,7 @@ endif()
 # Be really annoying.
 check_cxx_compiler_flag( "-Wpedantic" HAS_FLAG_WPEDANTIC )
 if ( HAS_FLAG_WPEDANTIC )
-    add_compile_options( "-Wpedantic" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wpedantic> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wpedantic" )
 endif()
@@ -69,7 +69,7 @@ endif()
 # Disallow warning on style order of declarations.
 check_cxx_compiler_flag( "-Wno-reorder" HAS_FLAG_WNO-REORDER )
 if ( HAS_FLAG_WNO-REORDER )
-    add_compile_options( "-Wno-reorder" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wno-reorder> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wno-reorder" )
 endif()
@@ -77,7 +77,7 @@ endif()
 # Suppress warning for incomplete field initialization.
 check_cxx_compiler_flag( "-Wno-missing-field-initializers" HAS_FLAG_WNO-MISSING-FIELD-INITIALIZERS )
 if ( HAS_FLAG_WNO-MISSING-FIELD-INITIALIZERS )
-    add_compile_options( "-Wno-missing-field-initializers" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wno-missing-field-initializers> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wno-missing-field-initializers" )
 endif()
@@ -85,7 +85,7 @@ endif()
 # Conform to style.
 check_cxx_compiler_flag( "-Wno-missing-braces" HAS_FLAG_WNO-MISSING-BRACES )
 if ( HAS_FLAG_WNO-MISSING-BRACES )
-    add_compile_options( "-Wno-missing-braces" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wno-missing-braces> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wno-missing-braces" )
 endif()
@@ -93,7 +93,7 @@ endif()
 # Ignore comments within comments or commenting of backslash extended lines.
 check_cxx_compiler_flag( "-Wno-comment" HAS_FLAG_WNO-COMMENT )
 if ( HAS_FLAG_WNO-COMMENT )
-    add_compile_options( "-Wno-comment" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wno-comment> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wno-comment" )
 endif()
@@ -101,7 +101,7 @@ endif()
 # Suppress warning for copy of implicitly generated copy constructor.
 check_cxx_compiler_flag( "-Wno-deprecated-copy" HAS_FLAG_WNO-DEPRECATED-COPY )
 if ( HAS_FLAG_WNO-DEPRECATED-COPY )
-    add_compile_options( "-Wno-deprecated-copy" )
+    add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wno-deprecated-copy> )
 else()
     message( FATAL_ERROR "Compiler does not support -Wno-deprecated-copy" )
 endif()
@@ -110,7 +110,7 @@ endif()
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
     check_cxx_compiler_flag( "-Wno-mismatched-tags" HAS_FLAG_WNO-MISMATCHED-TAGS )
     if ( HAS_FLAG_WNO-MISMATCHED-TAGS )
-        add_compile_options( "-Wno-mismatched-tags" )
+        add_compile_options( $<$<COMPILE_LANGUAGE:CXX>:-Wno-mismatched-tags> )
     else()
         message( FATAL_ERROR "Compiler does not support -Wno-mismatched-tags" )
     endif()
diff --git a/builds/cmake/CMakePresets.json b/builds/cmake/CMakePresets.json
index 26f1f13c..e77051f7 100644
--- a/builds/cmake/CMakePresets.json
+++ b/builds/cmake/CMakePresets.json
@@ -79,8 +79,8 @@
             "description": "Factored size optimization settings.",
             "hidden": true,
             "cacheVariables": {
-                "CMAKE_C_FLAGS": "$env{CMAKE_C_FLAGS} -Os -s",
-                "CMAKE_CXX_FLAGS": "$env{CMAKE_CXX_FLAGS} -Os -s"
+                "CMAKE_C_FLAGS": "$env{CMAKE_C_FLAGS} -Os",
+                "CMAKE_CXX_FLAGS": "$env{CMAKE_CXX_FLAGS} -Os"
             }
         },
         {
diff --git a/install-cmake.sh b/install-cmake.sh
index 40c454ba..5b895af1 100755
--- a/install-cmake.sh
+++ b/install-cmake.sh
@@ -900,6 +900,7 @@ build_from_tarball_boost()
         "$BOOST_CXXFLAGS" \
         "$BOOST_LINKFLAGS" \
         "link=$BOOST_LINK" \
+	"warnings=off" \
         "boost.locale.iconv=$BOOST_ICU_ICONV" \
         "boost.locale.posix=$BOOST_ICU_POSIX" \
         "-sNO_BZIP2=1" \
@@ -923,27 +924,62 @@ build_from_tarball_boost()
 build_all()
 {
     unpack_from_tarball "$ICU_ARCHIVE" "$ICU_URL" gzip "$BUILD_ICU"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${ICU_FLAGS[@]}"
     build_from_tarball "$ICU_ARCHIVE" source "$PARALLEL" "$BUILD_ICU" "${ICU_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS
+    export CPPFLAGS=$SAVE_CPPFLAGS
     unpack_from_tarball "$BOOST_ARCHIVE" "$BOOST_URL" bzip2 "$BUILD_BOOST"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BOOST_FLAGS[@]}"
     build_from_tarball_boost "$BOOST_ARCHIVE" "$PARALLEL" "$BUILD_BOOST" "${BOOST_OPTIONS[@]}"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin secp256k1 version7 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${SECP256K1_FLAGS[@]}"
     build_from_github secp256k1 "$PARALLEL" false "yes" "${SECP256K1_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-system version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SYSTEM_FLAGS[@]}"
     build_from_github_cmake libbitcoin-system "$PARALLEL" false "yes" "${BITCOIN_SYSTEM_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-database version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_DATABASE_FLAGS[@]}"
     build_from_github_cmake libbitcoin-database "$PARALLEL" false "yes" "${BITCOIN_DATABASE_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-consensus version3 "$WITH_BITCOIN_CONSENSUS"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_CONSENSUS_FLAGS[@]}"
     build_from_github_cmake libbitcoin-consensus "$PARALLEL" false "$WITH_BITCOIN_CONSENSUS" "${BITCOIN_CONSENSUS_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-blockchain version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_BLOCKCHAIN_FLAGS[@]}"
     build_from_github_cmake libbitcoin-blockchain "$PARALLEL" false "yes" "${BITCOIN_BLOCKCHAIN_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-network version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_NETWORK_FLAGS[@]}"
     build_from_github_cmake libbitcoin-network "$PARALLEL" false "yes" "${BITCOIN_NETWORK_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-node version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_NODE_FLAGS[@]}"
     build_from_github_cmake libbitcoin-node "$PARALLEL" false "yes" "${BITCOIN_NODE_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     unpack_from_tarball "$ZMQ_ARCHIVE" "$ZMQ_URL" gzip "$BUILD_ZMQ"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${ZMQ_FLAGS[@]}"
     build_from_tarball "$ZMQ_ARCHIVE" . "$PARALLEL" "$BUILD_ZMQ" "${ZMQ_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-protocol version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_PROTOCOL_FLAGS[@]}"
     build_from_github_cmake libbitcoin-protocol "$PARALLEL" false "yes" "${BITCOIN_PROTOCOL_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SERVER_FLAGS[@]}"
     if [[ ! ($CI == true) ]]; then
         create_from_github libbitcoin libbitcoin-server version3 "yes"
         build_from_github_cmake libbitcoin-server "$PARALLEL" true "yes" "${BITCOIN_SERVER_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
@@ -954,6 +990,7 @@ build_all()
         pop_directory
         pop_directory
     fi
+    export CPPFLAGS=$SAVE_CPPFLAGS
 }
 
 
@@ -975,6 +1012,24 @@ set_with_boost_prefix
 
 remove_install_options
 
+# Define build flags.
+#==============================================================================
+# Define icu flags.
+#------------------------------------------------------------------------------
+ICU_FLAGS=(
+"-w")
+
+# Define secp256k1 flags.
+#------------------------------------------------------------------------------
+SECP256K1_FLAGS=(
+"-w")
+
+# Define zmq flags.
+#------------------------------------------------------------------------------
+ZMQ_FLAGS=(
+"-w")
+
+
 # Define build options.
 #==============================================================================
 # Define icu options.
diff --git a/install-cmakepresets.sh b/install-cmakepresets.sh
index 7c0f8530..e013b7e0 100755
--- a/install-cmakepresets.sh
+++ b/install-cmakepresets.sh
@@ -961,6 +961,7 @@ build_from_tarball_boost()
         "$BOOST_CXXFLAGS" \
         "$BOOST_LINKFLAGS" \
         "link=$BOOST_LINK" \
+	"warnings=off" \
         "boost.locale.iconv=$BOOST_ICU_ICONV" \
         "boost.locale.posix=$BOOST_ICU_POSIX" \
         "-sNO_BZIP2=1" \
@@ -984,34 +985,69 @@ build_from_tarball_boost()
 build_all()
 {
     unpack_from_tarball "$ICU_ARCHIVE" "$ICU_URL" gzip "$BUILD_ICU"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${ICU_FLAGS[@]}"
     build_from_tarball "$ICU_ARCHIVE" source "$PARALLEL" "$BUILD_ICU" "${ICU_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS
+    export CPPFLAGS=$SAVE_CPPFLAGS
     unpack_from_tarball "$BOOST_ARCHIVE" "$BOOST_URL" bzip2 "$BUILD_BOOST"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BOOST_FLAGS[@]}"
     build_from_tarball_boost "$BOOST_ARCHIVE" "$PARALLEL" "$BUILD_BOOST" "${BOOST_OPTIONS[@]}"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin secp256k1 version7 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${SECP256K1_FLAGS[@]}"
     build_from_github secp256k1 "$PARALLEL" false "yes" "${SECP256K1_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-system version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SYSTEM_FLAGS[@]}"
     display_message "libbitcoin-system PRESET ${REPO_PRESET[libbitcoin-system]}"
     build_from_github_cmake libbitcoin-system ${REPO_PRESET[libbitcoin-system]} "$PARALLEL" false "yes" "${BITCOIN_SYSTEM_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-database version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_DATABASE_FLAGS[@]}"
     display_message "libbitcoin-database PRESET ${REPO_PRESET[libbitcoin-database]}"
     build_from_github_cmake libbitcoin-database ${REPO_PRESET[libbitcoin-database]} "$PARALLEL" false "yes" "${BITCOIN_DATABASE_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-consensus version3 "$WITH_BITCOIN_CONSENSUS"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_CONSENSUS_FLAGS[@]}"
     display_message "libbitcoin-consensus PRESET ${REPO_PRESET[libbitcoin-consensus]}"
     build_from_github_cmake libbitcoin-consensus ${REPO_PRESET[libbitcoin-consensus]} "$PARALLEL" false "$WITH_BITCOIN_CONSENSUS" "${BITCOIN_CONSENSUS_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-blockchain version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_BLOCKCHAIN_FLAGS[@]}"
     display_message "libbitcoin-blockchain PRESET ${REPO_PRESET[libbitcoin-blockchain]}"
     build_from_github_cmake libbitcoin-blockchain ${REPO_PRESET[libbitcoin-blockchain]} "$PARALLEL" false "yes" "${BITCOIN_BLOCKCHAIN_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-network version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_NETWORK_FLAGS[@]}"
     display_message "libbitcoin-network PRESET ${REPO_PRESET[libbitcoin-network]}"
     build_from_github_cmake libbitcoin-network ${REPO_PRESET[libbitcoin-network]} "$PARALLEL" false "yes" "${BITCOIN_NETWORK_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-node version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_NODE_FLAGS[@]}"
     display_message "libbitcoin-node PRESET ${REPO_PRESET[libbitcoin-node]}"
     build_from_github_cmake libbitcoin-node ${REPO_PRESET[libbitcoin-node]} "$PARALLEL" false "yes" "${BITCOIN_NODE_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     unpack_from_tarball "$ZMQ_ARCHIVE" "$ZMQ_URL" gzip "$BUILD_ZMQ"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${ZMQ_FLAGS[@]}"
     build_from_tarball "$ZMQ_ARCHIVE" . "$PARALLEL" "$BUILD_ZMQ" "${ZMQ_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-protocol version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_PROTOCOL_FLAGS[@]}"
     display_message "libbitcoin-protocol PRESET ${REPO_PRESET[libbitcoin-protocol]}"
     build_from_github_cmake libbitcoin-protocol ${REPO_PRESET[libbitcoin-protocol]} "$PARALLEL" false "yes" "${BITCOIN_PROTOCOL_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SERVER_FLAGS[@]}"
     if [[ ! ($CI == true) ]]; then
         create_from_github libbitcoin libbitcoin-server version3 "yes"
         display_message "libbitcoin-server PRESET ${REPO_PRESET[libbitcoin-server]}"
@@ -1024,6 +1060,7 @@ build_all()
         pop_directory
         pop_directory
     fi
+    export CPPFLAGS=$SAVE_CPPFLAGS
 }
 
 
@@ -1045,6 +1082,24 @@ set_with_boost_prefix
 
 remove_install_options
 
+# Define build flags.
+#==============================================================================
+# Define icu flags.
+#------------------------------------------------------------------------------
+ICU_FLAGS=(
+"-w")
+
+# Define secp256k1 flags.
+#------------------------------------------------------------------------------
+SECP256K1_FLAGS=(
+"-w")
+
+# Define zmq flags.
+#------------------------------------------------------------------------------
+ZMQ_FLAGS=(
+"-w")
+
+
 # Define build options.
 #==============================================================================
 # Define icu options.
diff --git a/install.sh b/install.sh
index fd358b00..2a17baf2 100755
--- a/install.sh
+++ b/install.sh
@@ -766,6 +766,7 @@ build_from_tarball_boost()
         "$BOOST_CXXFLAGS" \
         "$BOOST_LINKFLAGS" \
         "link=$BOOST_LINK" \
+	"warnings=off" \
         "boost.locale.iconv=$BOOST_ICU_ICONV" \
         "boost.locale.posix=$BOOST_ICU_POSIX" \
         "-sNO_BZIP2=1" \
@@ -789,27 +790,62 @@ build_from_tarball_boost()
 build_all()
 {
     unpack_from_tarball "$ICU_ARCHIVE" "$ICU_URL" gzip "$BUILD_ICU"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${ICU_FLAGS[@]}"
     build_from_tarball "$ICU_ARCHIVE" source "$PARALLEL" "$BUILD_ICU" "${ICU_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     unpack_from_tarball "$BOOST_ARCHIVE" "$BOOST_URL" bzip2 "$BUILD_BOOST"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BOOST_FLAGS[@]}"
     build_from_tarball_boost "$BOOST_ARCHIVE" "$PARALLEL" "$BUILD_BOOST" "${BOOST_OPTIONS[@]}"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin secp256k1 version7 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${SECP256K1_FLAGS[@]}"
     build_from_github secp256k1 "$PARALLEL" false "yes" "${SECP256K1_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-system version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SYSTEM_FLAGS[@]}"
     build_from_github libbitcoin-system "$PARALLEL" false "yes" "${BITCOIN_SYSTEM_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-database version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_DATABASE_FLAGS[@]}"
     build_from_github libbitcoin-database "$PARALLEL" false "yes" "${BITCOIN_DATABASE_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-consensus version3 "$WITH_BITCOIN_CONSENSUS"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_CONSENSUS_FLAGS[@]}"
     build_from_github libbitcoin-consensus "$PARALLEL" false "$WITH_BITCOIN_CONSENSUS" "${BITCOIN_CONSENSUS_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-blockchain version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_BLOCKCHAIN_FLAGS[@]}"
     build_from_github libbitcoin-blockchain "$PARALLEL" false "yes" "${BITCOIN_BLOCKCHAIN_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-network version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_NETWORK_FLAGS[@]}"
     build_from_github libbitcoin-network "$PARALLEL" false "yes" "${BITCOIN_NETWORK_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-node version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_NODE_FLAGS[@]}"
     build_from_github libbitcoin-node "$PARALLEL" false "yes" "${BITCOIN_NODE_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     unpack_from_tarball "$ZMQ_ARCHIVE" "$ZMQ_URL" gzip "$BUILD_ZMQ"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${ZMQ_FLAGS[@]}"
     build_from_tarball "$ZMQ_ARCHIVE" . "$PARALLEL" "$BUILD_ZMQ" "${ZMQ_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-protocol version3 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_PROTOCOL_FLAGS[@]}"
     build_from_github libbitcoin-protocol "$PARALLEL" false "yes" "${BITCOIN_PROTOCOL_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SERVER_FLAGS[@]}"
     if [[ ! ($CI == true) ]]; then
         create_from_github libbitcoin libbitcoin-server version3 "yes"
         build_from_github libbitcoin-server "$PARALLEL" true "yes" "${BITCOIN_SERVER_OPTIONS[@]}" "$@"
@@ -820,6 +856,7 @@ build_all()
         pop_directory
         pop_directory
     fi
+    export CPPFLAGS=$SAVE_CPPFLAGS
 }
 
 
@@ -840,6 +877,24 @@ set_pkgconfigdir
 set_with_boost_prefix
 
 
+# Define build flags.
+#==============================================================================
+# Define icu flags.
+#------------------------------------------------------------------------------
+ICU_FLAGS=(
+"-w")
+
+# Define secp256k1 flags.
+#------------------------------------------------------------------------------
+SECP256K1_FLAGS=(
+"-w")
+
+# Define zmq flags.
+#------------------------------------------------------------------------------
+ZMQ_FLAGS=(
+"-w")
+
+
 # Define build options.
 #==============================================================================
 # Define icu options.