diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 47e38227..1f8282bf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -187,9 +187,10 @@ jobs:
 
       - name: Coveralls.io Upload
         if: ${{ matrix.coverage == 'cov' }}
-        uses: pmienk/coveralls-github-action@master
+        uses: coverallsapp/github-action@v2.2.3
         with:
-          path-to-lcov: "./coverage.info"
+          format: lcov
+          files: "./coverage.info"
           github-token: ${{ secrets.github_token }}
 
       - name: Failure display available binaries
@@ -420,9 +421,10 @@ jobs:
 
       - name: Coveralls.io Upload
         if: ${{ matrix.coverage == 'cov' }}
-        uses: pmienk/coveralls-github-action@master
+        uses: coverallsapp/github-action@v2.2.3
         with:
-          path-to-lcov: "./coverage.info"
+          format: lcov
+          files: "./coverage.info"
           github-token: ${{ secrets.github_token }}
 
       - name: Failure display available binaries
@@ -622,9 +624,10 @@ jobs:
 
       - name: Coveralls.io Upload
         if: ${{ matrix.coverage == 'cov' }}
-        uses: pmienk/coveralls-github-action@master
+        uses: coverallsapp/github-action@v2.2.3
         with:
-          path-to-lcov: "./coverage.info"
+          format: lcov
+          files: "./coverage.info"
           github-token: ${{ secrets.github_token }}
 
       - name: Failure display available binaries
@@ -707,7 +710,7 @@ jobs:
 
     steps:
       - name: Add msbuild to PATH
-        uses: microsoft/setup-msbuild@v1.1
+        uses: microsoft/setup-msbuild@v2
         with:
           msbuild-architecture: x64
 
@@ -737,7 +740,7 @@ jobs:
           }
 
       - name: Execute build
-        run: .\build.cmd .. ${{ matrix.platform }} ${{ matrix.configuration }} ${{ matrix.version }}
+        run: .\build.cmd .. ${{ matrix.platform }} ${{ matrix.configuration }} x64 ${{ matrix.version }}
 
       - name: Execute tests
         shell: powershell
diff --git a/build.cmd b/build.cmd
index 79054ed8..b2cee3e3 100644
--- a/build.cmd
+++ b/build.cmd
@@ -11,10 +11,10 @@ SET "relative_path_base=%~1"
 call cd /d "%relative_path_base%"
 SET "path_base=%cd%"
 SET "nuget_pkg_path=%path_base%\.nuget\packages"
-SET "msbuild_args=/verbosity:minimal /p:Platform=%~2 /p:Configuration=%~3"
-SET "proj_version=%~4"
+SET "msbuild_args=/verbosity:minimal /p:Platform=%~2 /p:Configuration=%~3 /p:PreferredToolArchitecture=%~4"
+SET "proj_version=%~5"
 SET "msbuild_exe=msbuild"
-IF EXIST "%~5" SET "msbuild_exe=%~5"
+IF EXIST "%~6" SET "msbuild_exe=%~6"
 
 call :pending "Build initialized..."
 IF NOT EXIST "%nuget_pkg_path%" (
diff --git a/builds/cmake/CMakeLists.txt b/builds/cmake/CMakeLists.txt
index 288b6657..8536d150 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()
 # 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()
@@ -69,7 +69,7 @@ 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()
@@ -77,7 +77,7 @@ 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()
@@ -85,7 +85,7 @@ 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()
@@ -93,7 +93,7 @@ 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()
@@ -102,7 +102,7 @@ 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 f59a6e7a..b22d9003 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 58581857..1363616e 100755
--- a/install-cmake.sh
+++ b/install-cmake.sh
@@ -873,7 +873,12 @@ build_from_tarball_boost()
     display_message "BOOST_OPTIONS         : $*"
     display_message "--------------------------------------------------------------------"
 
+    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
+    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
+    cp tools/build/src/engine/b2 .
+
     ./bootstrap.sh \
+        "--with-bjam=./b2" \
         "--prefix=$PREFIX" \
         "--with-icu=$ICU_PREFIX"
 
@@ -891,6 +896,7 @@ build_from_tarball_boost()
         "$BOOST_CXXFLAGS" \
         "$BOOST_LINKFLAGS" \
         "link=$BOOST_LINK" \
+	"warnings=off" \
         "boost.locale.iconv=$BOOST_ICU_ICONV" \
         "boost.locale.posix=$BOOST_ICU_POSIX" \
         "-sNO_BZIP2=1" \
@@ -914,17 +920,37 @@ build_from_tarball_boost()
 build_all()
 {
     unpack_from_tarball "$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 version8 "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 master "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=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-database master "yes"
+    local SAVE_CPPFLAGS="$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=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-consensus master "$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=$SAVE_CPPFLAGS
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_BLOCKCHAIN_FLAGS[@]}"
     if [[ ! ($CI == true) ]]; then
         create_from_github libbitcoin libbitcoin-blockchain master "yes"
         build_from_github_cmake libbitcoin-blockchain "$PARALLEL" true "yes" "${BITCOIN_BLOCKCHAIN_OPTIONS[@]}" $CUMULATIVE_FILTERED_ARGS_CMAKE "$@"
@@ -935,6 +961,7 @@ build_all()
         pop_directory
         pop_directory
     fi
+    export CPPFLAGS=$SAVE_CPPFLAGS
 }
 
 
@@ -956,6 +983,19 @@ set_with_boost_prefix
 
 remove_install_options
 
+# Define build flags.
+#==============================================================================
+# Define icu flags.
+#------------------------------------------------------------------------------
+ICU_FLAGS=(
+"-w")
+
+# Define secp256k1 flags.
+#------------------------------------------------------------------------------
+SECP256K1_FLAGS=(
+"-w")
+
+
 # Define build options.
 #==============================================================================
 # Define icu options.
diff --git a/install-cmakepresets.sh b/install-cmakepresets.sh
index 072de3f1..6ae3ee0f 100755
--- a/install-cmakepresets.sh
+++ b/install-cmakepresets.sh
@@ -938,7 +938,12 @@ build_from_tarball_boost()
     display_message "BOOST_OPTIONS         : $*"
     display_message "--------------------------------------------------------------------"
 
+    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
+    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
+    cp tools/build/src/engine/b2 .
+
     ./bootstrap.sh \
+        "--with-bjam=./b2" \
         "--prefix=$PREFIX" \
         "--with-icu=$ICU_PREFIX"
 
@@ -956,6 +961,7 @@ build_from_tarball_boost()
         "$BOOST_CXXFLAGS" \
         "$BOOST_LINKFLAGS" \
         "link=$BOOST_LINK" \
+	"warnings=off" \
         "boost.locale.iconv=$BOOST_ICU_ICONV" \
         "boost.locale.posix=$BOOST_ICU_POSIX" \
         "-sNO_BZIP2=1" \
@@ -979,20 +985,40 @@ build_from_tarball_boost()
 build_all()
 {
     unpack_from_tarball "$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 version8 "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 master "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=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-database master "yes"
+    local SAVE_CPPFLAGS="$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=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-consensus master "$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=$SAVE_CPPFLAGS
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_BLOCKCHAIN_FLAGS[@]}"
     if [[ ! ($CI == true) ]]; then
         create_from_github libbitcoin libbitcoin-blockchain master "yes"
         display_message "libbitcoin-blockchain PRESET ${REPO_PRESET[libbitcoin-blockchain]}"
@@ -1005,6 +1031,7 @@ build_all()
         pop_directory
         pop_directory
     fi
+    export CPPFLAGS=$SAVE_CPPFLAGS
 }
 
 
@@ -1026,6 +1053,19 @@ set_with_boost_prefix
 
 remove_install_options
 
+# Define build flags.
+#==============================================================================
+# Define icu flags.
+#------------------------------------------------------------------------------
+ICU_FLAGS=(
+"-w")
+
+# Define secp256k1 flags.
+#------------------------------------------------------------------------------
+SECP256K1_FLAGS=(
+"-w")
+
+
 # Define build options.
 #==============================================================================
 # Define icu options.
diff --git a/install.sh b/install.sh
index 62c70d38..dd56d0d6 100755
--- a/install.sh
+++ b/install.sh
@@ -739,7 +739,12 @@ build_from_tarball_boost()
     display_message "BOOST_OPTIONS         : $*"
     display_message "--------------------------------------------------------------------"
 
+    guessed_toolset=`./tools/build/src/engine/build.sh --guess-toolset`
+    CXXFLAGS="-w" ./tools/build/src/engine/build.sh ${guessed_toolset} --cxxflags="-w"
+    cp tools/build/src/engine/b2 .
+
     ./bootstrap.sh \
+        "--with-bjam=./b2" \
         "--prefix=$PREFIX" \
         "--with-icu=$ICU_PREFIX"
 
@@ -757,6 +762,7 @@ build_from_tarball_boost()
         "$BOOST_CXXFLAGS" \
         "$BOOST_LINKFLAGS" \
         "link=$BOOST_LINK" \
+	"warnings=off" \
         "boost.locale.iconv=$BOOST_ICU_ICONV" \
         "boost.locale.posix=$BOOST_ICU_POSIX" \
         "-sNO_BZIP2=1" \
@@ -780,17 +786,37 @@ build_from_tarball_boost()
 build_all()
 {
     unpack_from_tarball "$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 version8 "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${SECP256K1_FLAGS[@]}"
     build_from_github secp256k1 "$PARALLEL" false "yes" "${SECP256K1_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-system master "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_SYSTEM_FLAGS[@]}"
     build_from_github libbitcoin-system "$PARALLEL" false "yes" "${BITCOIN_SYSTEM_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-database master "yes"
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_DATABASE_FLAGS[@]}"
     build_from_github libbitcoin-database "$PARALLEL" false "yes" "${BITCOIN_DATABASE_OPTIONS[@]}" "$@"
+    export CPPFLAGS=$SAVE_CPPFLAGS
     create_from_github libbitcoin libbitcoin-consensus master "$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
+    local SAVE_CPPFLAGS="$CPPFLAGS"
+    export CPPFLAGS="$CPPFLAGS ${BITCOIN_BLOCKCHAIN_FLAGS[@]}"
     if [[ ! ($CI == true) ]]; then
         create_from_github libbitcoin libbitcoin-blockchain master "yes"
         build_from_github libbitcoin-blockchain "$PARALLEL" true "yes" "${BITCOIN_BLOCKCHAIN_OPTIONS[@]}" "$@"
@@ -801,6 +827,7 @@ build_all()
         pop_directory
         pop_directory
     fi
+    export CPPFLAGS=$SAVE_CPPFLAGS
 }
 
 
@@ -821,6 +848,19 @@ set_pkgconfigdir
 set_with_boost_prefix
 
 
+# Define build flags.
+#==============================================================================
+# Define icu flags.
+#------------------------------------------------------------------------------
+ICU_FLAGS=(
+"-w")
+
+# Define secp256k1 flags.
+#------------------------------------------------------------------------------
+SECP256K1_FLAGS=(
+"-w")
+
+
 # Define build options.
 #==============================================================================
 # Define icu options.