[folly] Do not use -Werror

ports/folly/no-werror.patch

@@ -0,0 +1,12 @@
+diff --git a/CMake/FollyCompilerUnix.cmake b/CMake/FollyCompilerUnix.cmake
+index b7d994b..a518cbe 100644
+--- a/CMake/FollyCompilerUnix.cmake
++++ b/CMake/FollyCompilerUnix.cmake
+@@ -16,7 +16,6 @@ function(apply_folly_compile_options_to_target THETARGET)
+       -std=gnu++14
+       -finput-charset=UTF-8
+       -fsigned-char
+-      -Werror
+       -Wall
+       -Wno-deprecated
+       -Wdeprecated-declarations

ports/folly/portfile.cmake

@@ -12,7 +12,7 @@ include(vcpkg_common_functions)
 # Required to run build/generate_escape_tables.py et al.
 vcpkg_find_acquire_program(PYTHON3)
 get_filename_component(PYTHON3_DIR "${PYTHON3}" DIRECTORY)
-set(ENV{PATH} "$ENV{PATH};${PYTHON3_DIR}")
+vcpkg_add_to_path("${PYTHON3_DIR}")
 
 vcpkg_from_github(
     OUT_SOURCE_PATH SOURCE_PATH
@@ -21,7 +21,8 @@ vcpkg_from_github(
     SHA512 38e7b713572d4af0a6453d001eddc32c74b4ec100158300c0a3a61a88ec546b449f1973c2b624273da4278173782aa71695d981dba3c8f423f5b76ed1375d286
     HEAD_REF master
     PATCHES
-        ${CMAKE_CURRENT_LIST_DIR}/find-gflags.patch
+        find-gflags.patch
+        no-werror.patch
 )
 
 file(COPY

scripts/cmake/vcpkg_append_to_path.cmake

@@ -0,0 +1,41 @@
+## # vcpkg_add_to_path
+##
+## Add a directory to the PATH environment variable
+##
+## ## Usage
+## ```cmake
+## vcpkg_add_to_path([PREPEND] <${PYTHON3_DIR}>)
+## ```
+##
+## ## Parameters
+## ### <positional>
+## The directory to add
+##
+## ### PREPEND
+## Prepends the directory.
+##
+## The default is to append.
+function(vcpkg_add_to_path)
+    if(NOT "${ARGC}" STREQUAL "1" AND NOT "${ARGC}" STREQUAL "2")
+        message(FATAL_ERROR "vcpkg_add_to_path() only accepts 1 or 2 arguments.")
+    endif()
+    if("${ARGV0}" STREQUAL "PREPEND")
+        if(NOT "${ARGC}" STREQUAL "2")
+            message(FATAL_ERROR "Expected second argument.")
+        endif()
+        if(CMAKE_HOST_WIN32)
+            set(ENV{PATH} "${ARGV1};$ENV{PATH}")
+        else()
+            set(ENV{PATH} "${ARGV1}:$ENV{PATH}")
+        endif()
+    else()
+        if(NOT "${ARGC}" STREQUAL "1")
+            message(FATAL_ERROR "Unexpected second argument: ${ARGV1}")
+        endif()
+        if(CMAKE_HOST_WIN32)
+            set(ENV{PATH} "$ENV{PATH};${ARGV0}")
+        else()
+            set(ENV{PATH} "$ENV{PATH}:${ARGV0}")
+        endif()
+    endif()
+endfunction()

scripts/cmake/vcpkg_common_functions.cmake

@@ -1,4 +1,5 @@
 include(vcpkg_acquire_msys)
+include(vcpkg_append_to_path)
 include(vcpkg_check_linkage)
 include(vcpkg_download_distfile)
 include(vcpkg_extract_source_archive)
@@ -24,4 +25,4 @@ include(vcpkg_copy_tool_dependencies)
 include(vcpkg_get_program_files_32_bit)
 include(vcpkg_get_program_files_platform_bitness)
 include(vcpkg_get_windows_sdk)
-include(vcpkg_replace_string)
+include(vcpkg_replace_string)