[icu] Enable parallel builds (#6695)

* Add VCPKG_NUM_LOGICAL_CORES

* break out logic that retries running a command several times into its own function

* Parallelize icu

8 files changed, 220 insertions, 134 deletions

diff --git a/ports/icu/fix_parallel_build_on_windows.patch b/ports/icu/fix_parallel_build_on_windows.patch
new file mode 100644
index 000000000..b0ea7556c
--- /dev/null
+++ b/ports/icu/fix_parallel_build_on_windows.patch
@@ -0,0 +1,13 @@
+diff --git a/source/data/Makefile.in b/source/data/Makefile.in
+index 1140b69..936ef81 100644
+--- a/source/data/Makefile.in
++++ b/source/data/Makefile.in
+@@ -514,7 +514,7 @@ build-dir:
+ # The | is an order-only prerequisite. This helps when the -j option is used,
+ # and we don't want the files to be built before the directories are built.
+ ifneq ($(filter order-only,$(.FEATURES)),)
+-$(ALL_FILES) $(ALL_INDEX_SRC_FILES): | build-dir
++$(ALL_FILES) $(ALL_INDEX_SRC_FILES) $(SO_VERSION_DATA): | build-dir
+ endif
+ 
+ # Now, sections for building each kind of data.
diff --git a/ports/icu/portfile.cmake b/ports/icu/portfile.cmake
index 2061111e9..9225246f3 100644
--- a/ports/icu/portfile.cmake
+++ b/ports/icu/portfile.cmake
@@ -15,11 +15,13 @@ vcpkg_download_distfile(
     FILENAME "icu4c-${VERSION2}-src.tgz"

     SHA512 4c37691246db802e4bae0c8c5f6ac1dac64c5753b607e539c5c1c36e361fcd9dd81bd1d3b5416c2960153b83700ccdb356412847d0506ab7782ae626ac0ffb94

 )

-vcpkg_extract_source_archive(${ARCHIVE} ${CURRENT_BUILDTREES_DIR}/src/icu-${VERSION})

-

-vcpkg_apply_patches(SOURCE_PATH ${SOURCE_PATH}

-    PATCHES ${CMAKE_CURRENT_LIST_DIR}/disable-escapestr-tool.patch

-            ${CMAKE_CURRENT_LIST_DIR}/remove-MD-from-configure.patch

+vcpkg_extract_source_archive_ex(

+    OUT_SOURCE_PATH SOURCE_PATH

+    ARCHIVE ${ARCHIVE}

+    PATCHES

+        ${CMAKE_CURRENT_LIST_DIR}/disable-escapestr-tool.patch

+        ${CMAKE_CURRENT_LIST_DIR}/remove-MD-from-configure.patch

+        ${CMAKE_CURRENT_LIST_DIR}/fix_parallel_build_on_windows.patch

 )

 

 set(CONFIGURE_OPTIONS "--disable-samples --disable-tests")

@@ -94,8 +96,8 @@ else()
         message(STATUS "Configuring ${TARGET_TRIPLET}-rel")

         file(REMOVE_RECURSE ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel)

         file(MAKE_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel)

-        set(ENV{CFLAGS} "${ICU_RUNTIME} -O2 -Oi -Zi ${VCPKG_C_FLAGS} ${VCPKG_C_FLAGS_RELEASE}")

-        set(ENV{CXXFLAGS} "${ICU_RUNTIME} -O2 -Oi -Zi ${VCPKG_CXX_FLAGS} ${VCPKG_CXX_FLAGS_RELEASE}")

+        set(ENV{CFLAGS} "${ICU_RUNTIME} -O2 -Oi -Zi -FS ${VCPKG_C_FLAGS} ${VCPKG_C_FLAGS_RELEASE}")

+        set(ENV{CXXFLAGS} "${ICU_RUNTIME} -O2 -Oi -Zi -FS ${VCPKG_CXX_FLAGS} ${VCPKG_CXX_FLAGS_RELEASE}")

         set(ENV{LDFLAGS} "-DEBUG -INCREMENTAL:NO -OPT:REF -OPT:ICF")

         vcpkg_execute_required_process(

             COMMAND ${BASH} --noprofile --norc -c

@@ -110,8 +112,8 @@ else()
         message(STATUS "Configuring ${TARGET_TRIPLET}-dbg")

         file(REMOVE_RECURSE ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg)

         file(MAKE_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg)

-        set(ENV{CFLAGS} "${ICU_RUNTIME}d -Od -Zi -RTC1 ${VCPKG_C_FLAGS} ${VCPKG_C_FLAGS_DEBUG}")

-        set(ENV{CXXFLAGS} "${ICU_RUNTIME}d -Od -Zi -RTC1 ${VCPKG_CXX_FLAGS} ${VCPKG_CXX_FLAGS_DEBUG}")

+        set(ENV{CFLAGS} "${ICU_RUNTIME}d -Od -Zi -FS -RTC1 ${VCPKG_C_FLAGS} ${VCPKG_C_FLAGS_DEBUG}")

+        set(ENV{CXXFLAGS} "${ICU_RUNTIME}d -Od -Zi -FS -RTC1 ${VCPKG_CXX_FLAGS} ${VCPKG_CXX_FLAGS_DEBUG}")

         set(ENV{LDFLAGS} "-DEBUG")

         vcpkg_execute_required_process(

             COMMAND ${BASH} --noprofile --norc -c

@@ -129,20 +131,32 @@ unset(ENV{LDFLAGS})
 if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL "release")

     # Build release

     message(STATUS "Package ${TARGET_TRIPLET}-rel")

-    vcpkg_execute_required_process(

-        COMMAND ${BASH} --noprofile --norc -c "make && make install"

+    vcpkg_execute_build_process(

+        COMMAND ${BASH} --noprofile --norc -c "make -j ${VCPKG_CONCURRENCY}"

+        NO_PARALLEL_COMMAND ${BASH} --noprofile --norc -c "make"

+        WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel"

+        LOGNAME "make-build-${TARGET_TRIPLET}-rel")

+

+    vcpkg_execute_build_process(

+        COMMAND ${BASH} --noprofile --norc -c "make install"

         WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel"

-        LOGNAME "build-${TARGET_TRIPLET}-rel")

+        LOGNAME "make-install-${TARGET_TRIPLET}-rel")

     message(STATUS "Package ${TARGET_TRIPLET}-rel done")

 endif()

 

 if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL "debug")

     # Build debug

     message(STATUS "Package ${TARGET_TRIPLET}-dbg")

-    vcpkg_execute_required_process(

-        COMMAND ${BASH} --noprofile --norc -c "make && make install"

+    vcpkg_execute_build_process(

+        COMMAND ${BASH} --noprofile --norc -c "make -j ${VCPKG_CONCURRENCY}"

+        NO_PARALLEL_COMMAND ${BASH} --noprofile --norc -c "make"

+        WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg"

+        LOGNAME "make-build-${TARGET_TRIPLET}-dbg")

+

+    vcpkg_execute_build_process(

+        COMMAND ${BASH} --noprofile --norc -c "make install"

         WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg"

-        LOGNAME "build-${TARGET_TRIPLET}-dbg")

+        LOGNAME "make-install-${TARGET_TRIPLET}-dbg")

     message(STATUS "Package ${TARGET_TRIPLET}-dbg done")

 endif()

 

diff --git a/scripts/cmake/vcpkg_build_cmake.cmake b/scripts/cmake/vcpkg_build_cmake.cmake
index 3db6597b4..b110d2cc9 100644
--- a/scripts/cmake/vcpkg_build_cmake.cmake
+++ b/scripts/cmake/vcpkg_build_cmake.cmake
@@ -60,10 +60,6 @@ function(vcpkg_build_cmake)
         set(TARGET_PARAM)
     endif()
 
-    if(_bc_DISABLE_PARALLEL)
-        set(PARALLEL_ARG ${NO_PARALLEL_ARG})
-    endif()
-
     foreach(BUILDTYPE "debug" "release")
         if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL BUILDTYPE)
             if(BUILDTYPE STREQUAL "debug")
@@ -75,8 +71,6 @@ function(vcpkg_build_cmake)
             endif()
 
             message(STATUS "Building ${TARGET_TRIPLET}-${SHORT_BUILDTYPE}")
-            set(LOGPREFIX "${CURRENT_BUILDTREES_DIR}/${_bc_LOGFILE_ROOT}-${TARGET_TRIPLET}-${SHORT_BUILDTYPE}")
-            set(LOGS)
 
             if(_bc_ADD_BIN_TO_PATH)
                 set(_BACKUP_ENV_PATH "$ENV{PATH}")
@@ -91,121 +85,22 @@ function(vcpkg_build_cmake)
                     set(ENV{PATH} "${CURRENT_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/bin${_PATHSEP}$ENV{PATH}")
                 endif()
             endif()
-            execute_process(
-                COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${PARALLEL_ARG}
-                OUTPUT_FILE "${LOGPREFIX}-out.log"
-                ERROR_FILE "${LOGPREFIX}-err.log"
-                RESULT_VARIABLE error_code
-                WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE})
-            if(error_code)
-                file(READ "${LOGPREFIX}-out.log" out_contents)
-                file(READ "${LOGPREFIX}-err.log" err_contents)
-
-                if(out_contents)
-                    list(APPEND LOGS "${LOGPREFIX}-out.log")
-                endif()
-                if(err_contents)
-                    list(APPEND LOGS "${LOGPREFIX}-err.log")
-                endif()
-
-                if(out_contents MATCHES "LINK : fatal error LNK1102:" OR out_contents MATCHES " fatal error C1060: ")
-                    # The linker ran out of memory during execution. We will try continuing once more, with parallelism disabled.
-                    message(STATUS "Restarting Build ${TARGET_TRIPLET}-${SHORT_BUILDTYPE} without parallelism because memory exceeded")
-                    execute_process(
-                        COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${NO_PARALLEL_ARG}
-                        OUTPUT_FILE "${LOGPREFIX}-out-1.log"
-                        ERROR_FILE "${LOGPREFIX}-err-1.log"
-                        RESULT_VARIABLE error_code
-                        WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE})
-
-                    if(error_code)
-                        file(READ "${LOGPREFIX}-out-1.log" out_contents)
-                        file(READ "${LOGPREFIX}-err-1.log" err_contents)
-
-                        if(out_contents)
-                            list(APPEND LOGS "${LOGPREFIX}-out-1.log")
-                        endif()
-                        if(err_contents)
-                            list(APPEND LOGS "${LOGPREFIX}-err-1.log")
-                        endif()
-                    endif()
-                elseif(out_contents MATCHES ": No such file or directory")
-                    # WSL workaround - WSL occassionally fails with no such file or directory. Detect if we are running in WSL and restart.
-                    execute_process(COMMAND "uname" "-r"
-                        OUTPUT_VARIABLE UNAME_R ERROR_VARIABLE UNAME_R
-                        OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_STRIP_TRAILING_WHITESPACE)
-
-                    if (UNAME_R MATCHES "Microsoft")
-                        set(ITERATION 0)
-                        while (ITERATION LESS 10 AND out_contents MATCHES ": No such file or directory")
-                            MATH(EXPR ITERATION "${ITERATION}+1")
-                            message(STATUS "Restarting Build ${TARGET_TRIPLET}-${SHORT_BUILDTYPE} because of wsl subsystem issue. Iteration: ${ITERATION}")
-                            execute_process(
-                                COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS}
-                                OUTPUT_FILE "${LOGPREFIX}-out-${ITERATION}.log"
-                                ERROR_FILE "${LOGPREFIX}-err-${ITERATION}.log"
-                                RESULT_VARIABLE error_code
-                                WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE})
 
-                            if(error_code)
-                                file(READ "${LOGPREFIX}-out-${ITERATION}.log" out_contents)
-                                file(READ "${LOGPREFIX}-err-${ITERATION}.log" err_contents)
-
-                                if(out_contents)
-                                    list(APPEND LOGS "${LOGPREFIX}-out-${ITERATION}.log")
-                                endif()
-                                if(err_contents)
-                                    list(APPEND LOGS "${LOGPREFIX}-err-${ITERATION}.log")
-                                endif()
-                            else()
-                                break()
-                            endif()
-                        endwhile()
-                    endif()
-                elseif(out_contents MATCHES "mt : general error c101008d: " OR out_contents MATCHES "mt.exe : general error c101008d: ")
-                    # Antivirus workaround - occasionally files are locked and cause mt.exe to fail
-                    set(ITERATION 0)
-                    while (ITERATION LESS 3 AND (out_contents MATCHES "mt : general error c101008d: " OR out_contents MATCHES "mt.exe : general error c101008d: "))
-                        MATH(EXPR ITERATION "${ITERATION}+1")
-                        message(STATUS "Restarting Build ${TARGET_TRIPLET}-${SHORT_BUILDTYPE} because of mt.exe file locking issue. Iteration: ${ITERATION}")
-                        execute_process(
-                            COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${PARALLEL_ARG}
-                            OUTPUT_FILE "${LOGPREFIX}-out-${ITERATION}.log"
-                            ERROR_FILE "${LOGPREFIX}-err-${ITERATION}.log"
-                            RESULT_VARIABLE error_code
-                            WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE})
-
-                        if(error_code)
-                            file(READ "${LOGPREFIX}-out-${ITERATION}.log" out_contents)
-                            file(READ "${LOGPREFIX}-err-${ITERATION}.log" err_contents)
-
-                            if(out_contents)
-                                list(APPEND LOGS "${LOGPREFIX}-out-${ITERATION}.log")
-                            endif()
-                            if(err_contents)
-                                list(APPEND LOGS "${LOGPREFIX}-err-${ITERATION}.log")
-                            endif()
-                        else()
-                            break()
-                        endif()
-                    endwhile()
-                endif()
-
-                if(error_code)
-                    set(STRINGIFIED_LOGS)
-                    foreach(LOG ${LOGS})
-                        file(TO_NATIVE_PATH "${LOG}" NATIVE_LOG)
-                        list(APPEND STRINGIFIED_LOGS "    ${NATIVE_LOG}\n")
-                    endforeach()
-                    set(_eb_COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${PARALLEL_ARG})
-                    set(_eb_WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE})
-                    message(FATAL_ERROR
-                        "  Command failed: ${_eb_COMMAND}\n"
-                        "  Working Directory: ${_eb_WORKING_DIRECTORY}\n"
-                        "  See logs for more information:\n"
-                        ${STRINGIFIED_LOGS})
-                endif()
+            if (_bc_DISABLE_PARALLEL)
+                vcpkg_execute_build_process(
+                    COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${NO_PARALLEL_ARG}
+                    WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE}
+                    LOGNAME "${_bc_LOGFILE_ROOT}-${TARGET_TRIPLET}-${SHORT_BUILDTYPE}"
+                )
+            else()
+                vcpkg_execute_build_process(
+                    COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${PARALLEL_ARG}
+                    NO_PARALLEL_COMMAND ${CMAKE_COMMAND} --build . --config ${CONFIG} ${TARGET_PARAM} -- ${BUILD_ARGS} ${NO_PARALLEL_ARG}
+                    WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE}
+                    LOGNAME "${_bc_LOGFILE_ROOT}-${TARGET_TRIPLET}-${SHORT_BUILDTYPE}"
+                )
             endif()
+
             if(_bc_ADD_BIN_TO_PATH)
                 set(ENV{PATH} "${_BACKUP_ENV_PATH}")
             endif()
diff --git a/scripts/cmake/vcpkg_common_functions.cmake b/scripts/cmake/vcpkg_common_functions.cmake
index d66fc5eff..b99f8bee8 100644
--- a/scripts/cmake/vcpkg_common_functions.cmake
+++ b/scripts/cmake/vcpkg_common_functions.cmake
@@ -7,6 +7,7 @@ include(vcpkg_extract_source_archive)
 include(vcpkg_extract_source_archive_ex)
 include(vcpkg_execute_required_process)
 include(vcpkg_execute_required_process_repeat)
+include(vcpkg_execute_build_process)
 include(vcpkg_find_acquire_program)
 include(vcpkg_fixup_cmake_targets)
 include(vcpkg_from_github)
diff --git a/scripts/cmake/vcpkg_execute_build_process.cmake b/scripts/cmake/vcpkg_execute_build_process.cmake
new file mode 100644
index 000000000..f02aa296d
--- /dev/null
+++ b/scripts/cmake/vcpkg_execute_build_process.cmake
@@ -0,0 +1,138 @@
+## # vcpkg_execute_build_process
+##
+## Execute a required build process
+##
+## ## Usage
+## ```cmake
+## vcpkg_execute_build_process(
+##     COMMAND <cmd> [<args>...]
+##     [NO_PARALLEL_COMMAND <cmd> [<args>...]]
+##     WORKING_DIRECTORY </path/to/dir>
+##     LOGNAME <log_name>)
+## )
+## ```
+## ## Parameters
+## ### COMMAND
+## The command to be executed, along with its arguments.
+##
+## ### NO_PARALLEL_COMMAND
+## Optional parameter which specifies a non-parallel command to attempt if a
+## failure potentially due to parallelism is detected.
+##
+## ### WORKING_DIRECTORY
+## The directory to execute the command in.
+##
+## ### LOGNAME
+## The prefix to use for the log files.
+##
+## This should be a unique name for different triplets so that the logs don't
+## conflict when building multiple at once.
+##
+## ## Examples
+##
+## * [icu](https://github.com/Microsoft/vcpkg/blob/master/ports/icu/portfile.cmake)
+function(vcpkg_execute_build_process)
+    cmake_parse_arguments(_ebp "" "WORKING_DIRECTORY;LOGNAME" "COMMAND;NO_PARALLEL_COMMAND" ${ARGN})
+
+    set(LOG_OUT "${CURRENT_BUILDTREES_DIR}/${_ebp_LOGNAME}-out.log")
+    set(LOG_ERR "${CURRENT_BUILDTREES_DIR}/${_ebp_LOGNAME}-err.log")
+
+    execute_process(
+        COMMAND ${_ebp_COMMAND}
+        WORKING_DIRECTORY ${_ebp_WORKING_DIRECTORY}
+        OUTPUT_FILE ${LOG_OUT}
+        ERROR_FILE ${LOG_ERR}
+        RESULT_VARIABLE error_code
+    )
+
+    if(error_code)
+        file(READ ${LOG_OUT} out_contents)
+        file(READ ${LOG_ERR} err_contents)
+
+        if(out_contents)
+            list(APPEND LOGS ${LOG_OUT})
+        endif()
+        if(err_contents)
+            list(APPEND LOGS ${LOG_ERR})
+        endif()
+
+        if(out_contents MATCHES "LINK : fatal error LNK1102:" OR out_contents MATCHES " fatal error C1060: "
+           OR err_contents MATCHES "LINK : fatal error LNK1102:" OR err_contents MATCHES " fatal error C1060: ")
+            # The linker ran out of memory during execution. We will try continuing once more, with parallelism disabled.
+            message(STATUS "Restarting Build without parallelism because memory exceeded")
+            set(LOG_OUT "${CURRENT_BUILDTREES_DIR}/${_ebp_LOGNAME}-out-1.log")
+            set(LOG_ERR "${CURRENT_BUILDTREES_DIR}/${_ebp_LOGNAME}-err-1.log")
+
+            if(${_ebp_NO_PARALLEL_COMMAND})
+                execute_process(
+                    COMMAND ${_ebp_NO_PARALLEL_COMMAND}
+                    WORKING_DIRECTORY ${_ebp_WORKING_DIRECTORY}
+                    OUTPUT_FILE ${LOG_OUT}
+                    ERROR_FILE ${LOG_ERR}
+                    RESULT_VARIABLE error_code
+                )
+            else()
+                execute_process(
+                    COMMAND ${_ebp_COMMAND}
+                    WORKING_DIRECTORY ${_ebp_WORKING_DIRECTORY}
+                    OUTPUT_FILE ${LOG_OUT}
+                    ERROR_FILE ${LOG_ERR}
+                    RESULT_VARIABLE error_code
+                )
+            endif()
+
+            if(error_code)
+                file(READ ${LOG_OUT} out_contents)
+                file(READ ${LOG_ERR} err_contents)
+
+                if(out_contents)
+                    list(APPEND LOGS ${LOG_OUT})
+                endif()
+                if(err_contents)
+                    list(APPEND LOGS ${LOG_ERR})
+                endif()
+            endif()
+        elseif(out_contents MATCHES "mt : general error c101008d: " OR out_contents MATCHES "mt.exe : general error c101008d: ")
+            # Antivirus workaround - occasionally files are locked and cause mt.exe to fail
+            message(STATUS "mt.exe has failed. This may be the result of anti-virus. Disabling anti-virus on the buildtree folder may improve build speed")
+            set(ITERATION 0)
+            while (ITERATION LESS 3 AND (out_contents MATCHES "mt : general error c101008d: " OR out_contents MATCHES "mt.exe : general error c101008d: "))
+                MATH(EXPR ITERATION "${ITERATION}+1")
+                message(STATUS "Restarting Build ${TARGET_TRIPLET}-${SHORT_BUILDTYPE} because of mt.exe file locking issue. Iteration: ${ITERATION}")
+                execute_process(
+                    COMMAND ${_ebp_COMMAND}
+                    OUTPUT_FILE "${LOGPREFIX}-out-${ITERATION}.log"
+                    ERROR_FILE "${LOGPREFIX}-err-${ITERATION}.log"
+                    RESULT_VARIABLE error_code
+                    WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-${SHORT_BUILDTYPE})
+
+                if(error_code)
+                    file(READ "${LOGPREFIX}-out-${ITERATION}.log" out_contents)
+                    file(READ "${LOGPREFIX}-err-${ITERATION}.log" err_contents)
+
+                    if(out_contents)
+                        list(APPEND LOGS "${LOGPREFIX}-out-${ITERATION}.log")
+                    endif()
+                    if(err_contents)
+                        list(APPEND LOGS "${LOGPREFIX}-err-${ITERATION}.log")
+                    endif()
+                else()
+                    break()
+                endif()
+            endwhile()
+        endif()
+
+        if(error_code)
+            set(STRINGIFIED_LOGS)
+            foreach(LOG ${LOGS})
+                file(TO_NATIVE_PATH "${LOG}" NATIVE_LOG)
+                list(APPEND STRINGIFIED_LOGS "    ${NATIVE_LOG}\n")
+            endforeach()
+            message(FATAL_ERROR
+                "  Command failed: ${_ebp_COMMAND}\n"
+                "  Working Directory: ${_ebp_WORKING_DIRECTORY}\n"
+                "  See logs for more information:\n"
+                ${STRINGIFIED_LOGS})
+        endif(error_code)
+    endif(error_code)
+endfunction(vcpkg_execute_build_process)
diff --git a/toolsrc/include/vcpkg/base/system.h b/toolsrc/include/vcpkg/base/system.h
index 0245b684a..907a692a2 100644
--- a/toolsrc/include/vcpkg/base/system.h
+++ b/toolsrc/include/vcpkg/base/system.h
@@ -28,4 +28,6 @@ namespace vcpkg::System
     const Optional<fs::path>& get_program_files_32_bit();
 
     const Optional<fs::path>& get_program_files_platform_bitness();
+
+    int get_num_logical_cores();
 }
diff --git a/toolsrc/src/vcpkg/base/system.cpp b/toolsrc/src/vcpkg/base/system.cpp
index 48a701bfa..a11853524 100644
--- a/toolsrc/src/vcpkg/base/system.cpp
+++ b/toolsrc/src/vcpkg/base/system.cpp
@@ -596,6 +596,11 @@ namespace vcpkg
 #else
     void System::register_console_ctrl_handler() {}
 #endif
+
+    int System::get_num_logical_cores()
+    {
+        return std::thread::hardware_concurrency();
+    }
 }
 
 namespace vcpkg::Debug
diff --git a/toolsrc/src/vcpkg/build.cpp b/toolsrc/src/vcpkg/build.cpp
index 7bd6f467b..0a7c854b5 100644
--- a/toolsrc/src/vcpkg/build.cpp
+++ b/toolsrc/src/vcpkg/build.cpp
@@ -334,6 +334,23 @@ namespace vcpkg::Build
         return ret;

     }

 

+    static int get_concurrency()

+    {

+        static int concurrency = []{

+        auto user_defined_concurrency = System::get_environment_variable("VCPKG_MAX_CONCURRENCY");

+        if (user_defined_concurrency)

+        {

+            return std::stoi(user_defined_concurrency.value_or_exit(VCPKG_LINE_INFO));

+        }

+        else

+        {

+            return System::get_num_logical_cores() + 1;

+        }

+        }();

+

+        return concurrency;

+    }

+

     static ExtendedBuildResult do_build_package(const VcpkgPaths& paths,

                                                 const PreBuildInfo& pre_build_info,

                                                 const PackageSpec& spec,

@@ -372,6 +389,7 @@ namespace vcpkg::Build
             {"_VCPKG_DOWNLOAD_TOOL", to_string(config.build_package_options.download_tool)},

             {"FEATURES", Strings::join(";", config.feature_list)},

             {"ALL_FEATURES", all_features},

+            {"VCPKG_CONCURRENCY", std::to_string(get_concurrency())},

         };

 

         if (!System::get_environment_variable("VCPKG_FORCE_SYSTEM_BINARIES").has_value())