Switch the CMake in pico-blink-sdk+pico-w-blink-sdk to use CMake native Swift support (#99)

kubamracek · web-flow · commit ec33a9472b46 · 2025-03-25T16:25:35.000-07:00
diff --git a/harmony/README.md b/harmony/README.md
@@ -58,7 +58,7 @@ The firmware for Harmony is built using CMake and requires the Raspberry Pi Pico
 
 4.  Generate the build files using CMake:
     ```bash
-    cmake -B build -G Ninja .
+    cmake -B build -G Ninja . -DCMAKE_EXPORT_COMPILE_COMMANDS=On
     ```
 
 5.  Build the firmware:
diff --git a/pico-blink-sdk/CMakeLists.txt b/pico-blink-sdk/CMakeLists.txt
@@ -1,38 +1,45 @@
-cmake_minimum_required(VERSION 3.13)
+cmake_minimum_required(VERSION 3.29)
 include($ENV{PICO_SDK_PATH}/external/pico_sdk_import.cmake)
 
+set(CMAKE_Swift_COMPILATION_MODE wholemodule)
+set(CMAKE_Swift_COMPILER_WORKS YES)
+
 project(swift-blinky)
 pico_sdk_init()
-
-if(APPLE)
-execute_process(COMMAND xcrun -f swiftc OUTPUT_VARIABLE SWIFTC OUTPUT_STRIP_TRAILING_WHITESPACE)
-else()
-execute_process(COMMAND which swiftc OUTPUT_VARIABLE SWIFTC OUTPUT_STRIP_TRAILING_WHITESPACE)
-endif()
+enable_language(Swift)
 
 set(SWIFT_TARGET "armv6m-none-none-eabi") # default for rp2040
 
 if(PICO_PLATFORM STREQUAL "rp2350-arm-s")
     message(STATUS "PICO_PLATFORM is set to rp2350-arm-s, using armv7em")
     set(SWIFT_TARGET "armv7em-none-none-eabi")
-    list(APPEND CLANG_ARCH_ABI_FLAGS "-Xcc" "-mfloat-abi=soft")
+    list(APPEND CLANG_ARCH_ABI_FLAGS "-Xcc -mfloat-abi=soft")
 elseif(PICO_PLATFORM STREQUAL "rp2040")
     message(STATUS "PICO_PLATFORM is set to RP2040, using armv6m")
-    list(APPEND CLANG_ARCH_ABI_FLAGS "-Xcc" "-mfloat-abi=soft")
+    list(APPEND CLANG_ARCH_ABI_FLAGS "-Xcc -mfloat-abi=soft")
 elseif(PICO_PLATFORM STREQUAL "rp2350-riscv")
     message(STATUS "PICO_PLATFORM is set to rp2350-riscv, using riscv32.")
     set(SWIFT_TARGET "riscv32-none-none-eabi")
-    list(APPEND CLANG_ARCH_ABI_FLAGS "-Xcc" "-march=rv32imac_zicsr_zifencei_zba_zbb_zbs_zbkb" "-Xcc" "-mabi=ilp32")
+    list(APPEND CLANG_ARCH_ABI_FLAGS "-Xcc -march=rv32imac_zicsr_zifencei_zba_zbb_zbs_zbkb -Xcc -mabi=ilp32")
 endif()
 
-add_executable(swift-blinky)
+add_executable(swift-blinky
+    # Source files:
+    Main.swift
+)
+
+set_target_properties(swift-blinky PROPERTIES LINKER_LANGUAGE CXX)
 
 target_link_libraries(swift-blinky
     pico_stdlib hardware_uart hardware_gpio
 )
 
-# Gather compile definitions from all dependencies
+# Clear the default COMPILE_OPTIONS which include C specific compiler flags that the Swift compiler will not accept
+# Instead, set those options to only apply when compiling C code.
+set_target_properties(pico_standard_link PROPERTIES INTERFACE_COMPILE_OPTIONS "")
+target_compile_options(pico_standard_link INTERFACE "$<$<COMPILE_LANGUAGE:C>:SHELL: -ffunction-sections -fdata-sections>")
 
+# Gather C compile definitions from all dependencies
 set_property(GLOBAL PROPERTY visited_targets "")
 set_property(GLOBAL PROPERTY compilerdefs_list "")
 
@@ -42,20 +49,18 @@ function(gather_compile_definitions_recursive target)
     
     # make sure we don't visit the same target twice
     # and that we don't visit the special generator expressions
-    if (${target} MATCHES "\\$<" OR ${target} MATCHES "::@" OR ${target} IN_LIST visited_targets)
+    if (${target} MATCHES "\\\$<" OR ${target} MATCHES "::@" OR ${target} IN_LIST visited_targets)
         return()
     endif()
 
     # Append the target to visited_targets
     list(APPEND visited_targets ${target})
     set_property(GLOBAL PROPERTY visited_targets "${visited_targets}")
 
-    # Get the current value of compilerdefs_list
-    get_property(compilerdefs_list GLOBAL PROPERTY compilerdefs_list)
-
     get_target_property(target_definitions ${target} INTERFACE_COMPILE_DEFINITIONS)
     if (target_definitions)
         # Append the target definitions to compilerdefs_list
+        get_property(compilerdefs_list GLOBAL PROPERTY compilerdefs_list)
         list(APPEND compilerdefs_list ${target_definitions})
         set_property(GLOBAL PROPERTY compilerdefs_list "${compilerdefs_list}")
     endif()
@@ -71,35 +76,38 @@ endfunction()
 
 gather_compile_definitions_recursive(swift-blinky)
 get_property(COMPILE_DEFINITIONS GLOBAL PROPERTY compilerdefs_list)
+get_property(INCLUDES GLOBAL PROPERTY includes_list)
 
-# Parse compiler definitions into a format that swiftc can understand
+# Convert compiler definitions into a format that swiftc can understand
 list(REMOVE_DUPLICATES COMPILE_DEFINITIONS)
-list(PREPEND COMPILE_DEFINITIONS "")
+list(PREPEND COMPILE_DEFINITIONS "") # adds a semicolon at the beginning
 string(REPLACE "$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>" "$<TARGET_PROPERTY:swift-blinky,PICO_TARGET_BINARY_TYPE>" COMPILE_DEFINITIONS "${COMPILE_DEFINITIONS}")
-string(REPLACE ";" ";-Xcc;-D" COMPILE_DEFINITIONS "${COMPILE_DEFINITIONS}")
-
-add_custom_command(
-    OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o
-    COMMAND
-        ${SWIFTC}
-        -target ${SWIFT_TARGET} -Xcc -fshort-enums
-        ${COMPILE_DEFINITIONS}
+string(REPLACE ";" " -Xcc -D" COMPILE_DEFINITIONS "${COMPILE_DEFINITIONS}")
+
+# Compute -Xcc flags to set up the C and C++ header search paths for Swift (for bridging header).
+set(IMPLICIT_INCLUDES)
+foreach(dir ${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES})
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-Xcc ")
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-I${dir} ")
+endforeach()
+foreach(dir ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-Xcc ")
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-I${dir} ")
+endforeach()
+
+target_compile_options(swift-blinky PUBLIC
+    "$<$<COMPILE_LANGUAGE:Swift>:SHELL:
+        -target ${SWIFT_TARGET}
+        -enable-experimental-feature Embedded
+        -parse-as-library
+        -module-name swift_blinky
+        
         ${CLANG_ARCH_ABI_FLAGS}
-        -Xfrontend -function-sections -enable-experimental-feature Embedded -wmo -parse-as-library
-        $$\( echo '$<TARGET_PROPERTY:swift-blinky,INCLUDE_DIRECTORIES>' | tr '\;' '\\n' | sed -e 's/\\\(.*\\\)/-Xcc -I\\1/g' \)
-        $$\( echo '${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES}'             | tr ' '  '\\n' | sed -e 's/\\\(.*\\\)/-Xcc -I\\1/g' \)
+        -Xcc -fshort-enums
+        -Xfrontend -function-sections
         -import-bridging-header ${CMAKE_CURRENT_LIST_DIR}/BridgingHeader.h
-        ${CMAKE_CURRENT_LIST_DIR}/Main.swift
-        -c -o ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o
-    DEPENDS
-        ${CMAKE_CURRENT_LIST_DIR}/BridgingHeader.h
-        ${CMAKE_CURRENT_LIST_DIR}/Main.swift
-)
-add_custom_target(swift-blinky-swiftcode DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o)
-
+        ${COMPILE_DEFINITIONS}
+        ${IMPLICIT_INCLUDES}
+    >")
 
-target_link_libraries(swift-blinky
-    ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o
-)
-add_dependencies(swift-blinky swift-blinky-swiftcode)
 pico_add_extra_outputs(swift-blinky)
diff --git a/pico-blink-sdk/README.md b/pico-blink-sdk/README.md
@@ -28,7 +28,7 @@ $ export PICO_BOARD='<board-name>' # Examples: pico, pico2
 $ export PICO_PLATFORM='<optional-platform-name>' # Optional; useful if you'd like to compile for RISC-V. Examples: rp2040, rp2350-arm-s, rp2350-riscv 
 $ export PICO_SDK_PATH='<path-to-your-pico-sdk>'
 $ export PICO_TOOLCHAIN_PATH='<path-to-the-compiler-toolchain>' # A default `brew` install will be located at `/Applications/ArmGNUToolchain/[version]/arm-none-eabi`. This can also be a RISC-V toolchain for the RP2350.
-$ cmake -B build -G Ninja .
+$ cmake -B build -G Ninja . -DCMAKE_EXPORT_COMPILE_COMMANDS=On
 $ cmake --build build
 ```
 
diff --git a/pico-w-blink-sdk/CMakeLists.txt b/pico-w-blink-sdk/CMakeLists.txt
@@ -1,21 +1,30 @@
-cmake_minimum_required(VERSION 3.13)
+cmake_minimum_required(VERSION 3.29)
 include($ENV{PICO_SDK_PATH}/external/pico_sdk_import.cmake)
 
+set(CMAKE_Swift_COMPILATION_MODE wholemodule)
+set(CMAKE_Swift_COMPILER_WORKS YES)
+
 project(swift-blinky)
 pico_sdk_init()
+enable_language(Swift)
+
+add_executable(swift-blinky
+    # Source files:
+    Main.swift
+)
 
-if(APPLE)
-execute_process(COMMAND xcrun -f swiftc OUTPUT_VARIABLE SWIFTC OUTPUT_STRIP_TRAILING_WHITESPACE)
-else()
-execute_process(COMMAND which swiftc OUTPUT_VARIABLE SWIFTC OUTPUT_STRIP_TRAILING_WHITESPACE)
-endif()
+set_target_properties(swift-blinky PROPERTIES LINKER_LANGUAGE CXX)
 
-add_executable(swift-blinky)
 target_link_libraries(swift-blinky
     pico_stdlib hardware_uart hardware_gpio pico_lwip_arch pico_cyw43_arch_none
 )
 
-# Gather compile definitions from all dependencies
+# Clear the default COMPILE_OPTIONS which include C specific compiler flags that the Swift compiler will not accept
+# Instead, set those options to only apply when compiling C code.
+set_target_properties(pico_standard_link PROPERTIES INTERFACE_COMPILE_OPTIONS "")
+target_compile_options(pico_standard_link INTERFACE "$<$<COMPILE_LANGUAGE:C>:SHELL: -ffunction-sections -fdata-sections>")
+
+# Gather C compile definitions from all dependencies
 set_property(GLOBAL PROPERTY visited_targets "")
 set_property(GLOBAL PROPERTY compilerdefs_list "")
 
@@ -25,20 +34,18 @@ function(gather_compile_definitions_recursive target)
     
     # make sure we don't visit the same target twice
     # and that we don't visit the special generator expressions
-    if (${target} MATCHES "\\$<" OR ${target} MATCHES "::@" OR ${target} IN_LIST visited_targets)
+    if (${target} MATCHES "\\\$<" OR ${target} MATCHES "::@" OR ${target} IN_LIST visited_targets)
         return()
     endif()
 
     # Append the target to visited_targets
     list(APPEND visited_targets ${target})
     set_property(GLOBAL PROPERTY visited_targets "${visited_targets}")
 
-    # Get the current value of compilerdefs_list
-    get_property(compilerdefs_list GLOBAL PROPERTY compilerdefs_list)
-
     get_target_property(target_definitions ${target} INTERFACE_COMPILE_DEFINITIONS)
     if (target_definitions)
         # Append the target definitions to compilerdefs_list
+        get_property(compilerdefs_list GLOBAL PROPERTY compilerdefs_list)
         list(APPEND compilerdefs_list ${target_definitions})
         set_property(GLOBAL PROPERTY compilerdefs_list "${compilerdefs_list}")
     endif()
@@ -54,37 +61,37 @@ endfunction()
 
 gather_compile_definitions_recursive(swift-blinky)
 get_property(COMPILE_DEFINITIONS GLOBAL PROPERTY compilerdefs_list)
+get_property(INCLUDES GLOBAL PROPERTY includes_list)
 
-# Parse compiler definitions into a format that swiftc can understand
+# Convert compiler definitions into a format that swiftc can understand
 list(REMOVE_DUPLICATES COMPILE_DEFINITIONS)
 list(PREPEND COMPILE_DEFINITIONS "") # adds a semicolon at the beginning
 string(REPLACE "$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>" "$<TARGET_PROPERTY:swift-blinky,PICO_TARGET_BINARY_TYPE>" COMPILE_DEFINITIONS "${COMPILE_DEFINITIONS}")
-string(REPLACE ";" ";-Xcc;-D" COMPILE_DEFINITIONS "${COMPILE_DEFINITIONS}")
+string(REPLACE ";" " -Xcc -D" COMPILE_DEFINITIONS "${COMPILE_DEFINITIONS}")
 
-add_custom_command(
-    OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o
-    COMMAND
-        ${SWIFTC}
-        -target armv6m-none-none-eabi -Xcc -mfloat-abi=soft -Xcc -fshort-enums
-        ${COMPILE_DEFINITIONS}
-        -Xcc -DCYW43_LWIP
-        -Xcc -DPICO_CYW43_ARCH_THREADSAFE_BACKGROUND
-        -Xcc -I$ENV{PICO_SDK_PATH}/lib/lwip/src/include
-        -Xcc -I${CMAKE_CURRENT_LIST_DIR}/include
-        -Xfrontend -function-sections -enable-experimental-feature Embedded -wmo -parse-as-library
-        $$\( echo '$<TARGET_PROPERTY:swift-blinky,INCLUDE_DIRECTORIES>' | tr '\;' '\\n' | sed -e 's/\\\(.*\\\)/-Xcc -I\\1/g' \)
-        $$\( echo '${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES}'             | tr ' '  '\\n' | sed -e 's/\\\(.*\\\)/-Xcc -I\\1/g' \)
+# Compute -Xcc flags to set up the C and C++ header search paths for Swift (for bridging header).
+set(IMPLICIT_INCLUDES)
+foreach(dir ${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES})
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-Xcc ")
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-I${dir} ")
+endforeach()
+foreach(dir ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-Xcc ")
+    string(CONCAT IMPLICIT_INCLUDES ${IMPLICIT_INCLUDES} "-I${dir} ")
+endforeach()
+
+target_compile_options(swift-blinky PUBLIC
+    "$<$<COMPILE_LANGUAGE:Swift>:SHELL:
+        -target armv6m-none-none-eabi
+        -enable-experimental-feature Embedded
+        -parse-as-library
+        -module-name swift_blinky
+        
+        -Xcc -fshort-enums
+        -Xfrontend -function-sections
         -import-bridging-header ${CMAKE_CURRENT_LIST_DIR}/BridgingHeader.h
-        ${CMAKE_CURRENT_LIST_DIR}/Main.swift
-        -c -o ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o
-    DEPENDS
-        ${CMAKE_CURRENT_LIST_DIR}/BridgingHeader.h
-        ${CMAKE_CURRENT_LIST_DIR}/Main.swift
-)
-add_custom_target(swift-blinky-swiftcode DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o)
+        ${COMPILE_DEFINITIONS}
+        ${IMPLICIT_INCLUDES}
+    >")
 
-target_link_libraries(swift-blinky
-    ${CMAKE_CURRENT_BINARY_DIR}/_swiftcode.o
-)
-add_dependencies(swift-blinky swift-blinky-swiftcode)
 pico_add_extra_outputs(swift-blinky)
diff --git a/pico-w-blink-sdk/README.md b/pico-w-blink-sdk/README.md
@@ -26,7 +26,7 @@ $ export TOOLCHAINS='<toolchain-identifier>'
 $ export PICO_BOARD=pico_w
 $ export PICO_SDK_PATH='<path-to-your-pico-sdk>'
 $ export PICO_TOOLCHAIN_PATH='<path-to-the-arm-toolchain>'
-$ cmake -B build -G Ninja .
+$ cmake -B build -G Ninja . -DCMAKE_EXPORT_COMPILE_COMMANDS=On
 $ cmake --build build
 ```
 
