Merge branch 'feature/compiler_rt_support' into 'master'

build: Adds support for compiler-rt in Clang toolchain

See merge request espressif/esp-idf!21213

.gitlab-ci.yml

@@ -176,6 +176,15 @@ cache:
 
   source ./export.sh
 
+  # Custom clang
+  if [[ ! -z "$CI_CLANG_DISTRO_URL" ]]; then
+    echo "Using custom clang from ${CI_CLANG_DISTRO_URL}"
+    wget $CI_CLANG_DISTRO_URL
+    ARCH_NAME=$(basename $CI_CLANG_DISTRO_URL)
+    tar -x -f $ARCH_NAME
+    export PATH=$PWD/esp-clang/bin:$PATH
+  fi
+
   # Custom OpenOCD
   if [[ ! -z "$OOCD_DISTRO_URL" && "$CI_JOB_STAGE" == "target_test" ]]; then
     echo "Using custom OpenOCD from ${OOCD_DISTRO_URL}"

CMakeLists.txt

@@ -115,6 +115,8 @@ if(CMAKE_C_COMPILER_ID MATCHES "Clang")
     list(APPEND compile_options "-Wno-c2x-extensions")
     # warning on xMPU_SETTINGS for esp32s2 has size 0 for C and 1 for C++
     list(APPEND compile_options "-Wno-extern-c-compat")
+    # warning: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1
+    list(APPEND compile_options "-Wno-single-bit-bitfield-constant-conversion")
 endif()
 # More warnings may exist in unit tests and example projects.
 
@@ -222,6 +224,11 @@ endif()
 
 if(CMAKE_C_COMPILER_ID MATCHES "Clang")
     list(APPEND compile_options "-fno-use-cxa-atexit")
+    if(CONFIG_COMPILER_RT_LIB_GCCLIB)
+        list(APPEND link_options "-rtlib=libgcc")
+    elseif(CONFIG_COMPILER_RT_LIB_CLANGRT)
+        list(APPEND link_options "-rtlib=compiler-rt")
+    endif()
 endif()
 
 # For the transition period from 32-bit time_t to 64-bit time_t,

Kconfig

@@ -19,6 +19,18 @@ mainmenu "Espressif IoT Development Framework Configuration"
         bool
         default y if "$(IDF_CI_BUILD)" = "y" || "$(IDF_CI_BUILD)" = 1
 
+    config IDF_TOOLCHAIN
+        # This option records the IDF target when sdkconfig is generated the first time.
+        # It is not updated if environment variable $IDF_TOOLCHAIN changes later, and
+        # the build system is responsible for detecting the mismatch between
+        # CONFIG_IDF_TOOLCHAIN and $IDF_TOOLCHAIN.
+        string
+        default "$IDF_TOOLCHAIN"
+
+    config IDF_TOOLCHAIN_CLANG
+        bool
+        default "y" if IDF_TOOLCHAIN="clang"
+
     config IDF_TARGET_ARCH_RISCV
         bool
         default "n"
@@ -493,6 +505,27 @@ mainmenu "Espressif IoT Development Framework Configuration"
                 If enabled, RTL files will be produced during compilation. These files
                 can be used by other tools, for example to calculate call graphs.
 
+        choice COMPILER_RT_LIB
+            prompt "Compiler runtime library"
+            default COMPILER_RT_LIB_CLANGRT if IDF_TOOLCHAIN_CLANG
+            default COMPILER_RT_LIB_GCCLIB
+            help
+                Select runtime library to be used by compiler.
+                - GCC toolchain supports libgcc only.
+                - Clang allows to choose between libgcc or libclang_rt.
+
+            config COMPILER_RT_LIB_GCCLIB
+                bool "libgcc"
+            config COMPILER_RT_LIB_CLANGRT
+                depends on IDF_TOOLCHAIN_CLANG
+                bool "libclang_rt"
+        endchoice
+
+        config COMPILER_RT_LIB_NAME
+            string
+            default "clang_rt.builtins" if COMPILER_RT_LIB_CLANGRT
+            default "gcc" if COMPILER_RT_LIB_GCCLIB
+
     endmenu # Compiler Options
 
     menu "Component config"

components/app_trace/CMakeLists.txt

@@ -66,6 +66,12 @@ idf_component_register(SRCS "${srcs}"
 idf_component_get_property(app_trace app_trace COMPONENT_LIB)
 
 if(CONFIG_APPTRACE_GCOV_ENABLE)
+    if(CMAKE_C_COMPILER_ID MATCHES "Clang")
+        # Coverage info is not supported when clang is used
+        # TODO: LLVM-214
+        message(FATAL_ERROR "Coverage info is not supported when building with Clang!")
+    endif()
+
     # The original Gcov library from toolchain will be objcopy with symbols redefinitions (see file gcov/io_sym.map).
     # This needs because ESP has no file-system onboard, and redefined functions solves this problem and transmits
     # output file to host PC.

components/bootloader/subproject/main/ld/esp32/bootloader.ld

@@ -42,7 +42,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
      *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/bootloader/subproject/main/ld/esp32c2/bootloader.ld

@@ -63,7 +63,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
      *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/bootloader/subproject/main/ld/esp32c3/bootloader.ld

@@ -63,7 +63,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
     *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/bootloader/subproject/main/ld/esp32c6/bootloader.ld

@@ -60,7 +60,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
     *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/bootloader/subproject/main/ld/esp32h2/bootloader.ld

@@ -61,7 +61,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
     *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/bootloader/subproject/main/ld/esp32s2/bootloader.ld

@@ -29,7 +29,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
      *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/bootloader/subproject/main/ld/esp32s3/bootloader.ld

@@ -64,7 +64,9 @@ SECTIONS
     *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
      *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
     *liblog.a:(.literal .text .literal.* .text.*)
+    /* we use either libgcc or compiler-rt, so put similar entries for them here */
     *libgcc.a:(.literal .text .literal.* .text.*)
+    *libclang_rt.builtins.a:(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_clock_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_common_loader.*(.literal .text .literal.* .text.*)
     *libbootloader_support.a:bootloader_flash.*(.literal .text .literal.* .text.*)

components/cxx/CMakeLists.txt

@@ -43,7 +43,7 @@ endif()
 if(CMAKE_C_COMPILER_ID MATCHES "Clang")
     # libstdc++ depends on C library, so it should appear later in link order.
     # Otherwise we get undefined references for esp-clang toolchain.
-    target_link_libraries(${COMPONENT_LIB} PUBLIC stdc++ c gcc)
+    target_link_libraries(${COMPONENT_LIB} PUBLIC stdc++ c ${CONFIG_COMPILER_RT_LIB_NAME})
 else()
     target_link_libraries(${COMPONENT_LIB} PUBLIC stdc++ gcc)
 endif()
@@ -63,7 +63,7 @@ else()
 endif()
 target_link_libraries(${COMPONENT_LIB} PUBLIC stdcpp_pthread)
 add_library(libgcc_cxx INTERFACE)
-target_link_libraries(libgcc_cxx INTERFACE gcc $<TARGET_FILE:${cxx}>)
+target_link_libraries(libgcc_cxx INTERFACE ${CONFIG_COMPILER_RT_LIB_NAME} $<TARGET_FILE:${cxx}>)
 target_link_libraries(${COMPONENT_LIB} PUBLIC libgcc_cxx)
 
 if(NOT CONFIG_COMPILER_CXX_EXCEPTIONS)

components/efuse/esp32h2/esp_efuse_utility.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -115,24 +115,14 @@ esp_err_t esp_efuse_utility_burn_chip(void)
             if (esp_efuse_get_coding_scheme(num_block) == EFUSE_CODING_SCHEME_RS) {
                 uint8_t block_rs[12];
                 efuse_hal_rs_calculate((void *)range_write_addr_blocks[num_block].start, block_rs);
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wstringop-overflow"
-#pragma GCC diagnostic ignored "-Warray-bounds"
-                memcpy((void *)EFUSE_PGM_CHECK_VALUE0_REG, block_rs, sizeof(block_rs));
-#pragma GCC diagnostic pop
+                hal_memcpy((void *)EFUSE_PGM_CHECK_VALUE0_REG, block_rs, sizeof(block_rs));
             }
             unsigned r_data_len = (range_read_addr_blocks[num_block].end - range_read_addr_blocks[num_block].start) + sizeof(uint32_t);
             unsigned data_len = (range_write_addr_blocks[num_block].end - range_write_addr_blocks[num_block].start) + sizeof(uint32_t);
             memcpy((void *)EFUSE_PGM_DATA0_REG, (void *)range_write_addr_blocks[num_block].start, data_len);
 
             uint32_t backup_write_data[8 + 3]; // 8 words are data and 3 words are RS coding data
-#pragma GCC diagnostic push
-#if     __GNUC__ >= 11
-#pragma GCC diagnostic ignored "-Wstringop-overread"
-#endif
-#pragma GCC diagnostic ignored "-Warray-bounds"
-            memcpy(backup_write_data, (void *)EFUSE_PGM_DATA0_REG, sizeof(backup_write_data));
-#pragma GCC diagnostic pop
+            hal_memcpy(backup_write_data, (void *)EFUSE_PGM_DATA0_REG, sizeof(backup_write_data));
             int repeat_burn_op = 1;
             bool correct_written_data;
             bool coding_error_before = efuse_hal_is_coding_error_in_block(num_block);
@@ -161,11 +151,7 @@ esp_err_t esp_efuse_utility_burn_chip(void)
                 correct_written_data = esp_efuse_utility_is_correct_written_data(num_block, r_data_len);
                 if (!correct_written_data || coding_error_occurred) {
                     ESP_LOGW(TAG, "BLOCK%d: next retry to fix an error [%d/3]...", num_block, repeat_burn_op);
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wstringop-overflow"
-#pragma GCC diagnostic ignored "-Warray-bounds"
-                    memcpy((void *)EFUSE_PGM_DATA0_REG, (void *)backup_write_data, sizeof(backup_write_data));
-#pragma GCC diagnostic pop
+                    hal_memcpy((void *)EFUSE_PGM_DATA0_REG, (void *)backup_write_data, sizeof(backup_write_data));
                 }
 
             } while ((!correct_written_data || coding_error_occurred) && repeat_burn_op++ < 3);

components/newlib/CMakeLists.txt

@@ -36,7 +36,7 @@ idf_component_register(SRCS "${srcs}"
 
 # Toolchain libraries require code defined in this component
 idf_component_get_property(newlib newlib COMPONENT_LIB)
-target_link_libraries(${COMPONENT_LIB} INTERFACE c m gcc "$<TARGET_FILE:${newlib}>")
+target_link_libraries(${COMPONENT_LIB} INTERFACE c m ${CONFIG_COMPILER_RT_LIB_NAME} "$<TARGET_FILE:${newlib}>")
 
 set_source_files_properties(heap.c PROPERTIES COMPILE_FLAGS -fno-builtin)
 

components/newlib/system_libs.lf

@@ -7,6 +7,15 @@ entries:
     if IDF_TARGET_ARCH_RISCV:
         save-restore (noflash)
 
+[mapping:clang_rt_builtins]
+archive: libclang_rt.builtins.a
+entries:
+    if IDF_TARGET_ESP32 = n:
+        _divsf3 (noflash)
+    if IDF_TARGET_ARCH_RISCV:
+        save (noflash)
+        restore (noflash)
+
 [mapping:gcov]
 archive: libgcov.a
 entries:

tools/ci/check_ldgen_mapping_exceptions.txt

@@ -1,3 +1,4 @@
 libc
 sha256_coredump
 gcc
+clang_rt_builtins

tools/cmake/build.cmake

@@ -468,6 +468,8 @@ macro(idf_build_process target)
 
     idf_build_set_property(BOOTLOADER_BUILD "${BOOTLOADER_BUILD}")
 
+    idf_build_set_property(IDF_TOOLCHAIN "${IDF_TOOLCHAIN}")
+
     # Check build target is specified. Since this target corresponds to a component
     # name, the target component is automatically added to the list of common component
     # requirements.

tools/cmake/kconfig.cmake

@@ -94,6 +94,7 @@ function(__kconfig_generate_config sdkconfig sdkconfig_defaults)
     idf_build_set_property(KCONFIG_PROJBUILDS "${kconfig_projbuilds}")
 
     idf_build_get_property(idf_target IDF_TARGET)
+    idf_build_get_property(idf_toolchain IDF_TOOLCHAIN)
     idf_build_get_property(idf_path IDF_PATH)
     idf_build_get_property(idf_env_fpga __IDF_ENV_FPGA)
 
@@ -209,6 +210,7 @@ function(__kconfig_generate_config sdkconfig sdkconfig_defaults)
         COMMAND ${prepare_kconfig_files_command}
         COMMAND ${kconfgen_basecommand}
         --env "IDF_TARGET=${idf_target}"
+        --env "IDF_TOOLCHAIN=${idf_toolchain}"
         --env "IDF_ENV_FPGA=${idf_env_fpga}"
         --dont-write-deprecated
         --output config ${sdkconfig}
@@ -218,13 +220,15 @@ function(__kconfig_generate_config sdkconfig sdkconfig_defaults)
         "COMPONENT_KCONFIGS_PROJBUILD_SOURCE_FILE=${kconfigs_projbuild_path}"
         "KCONFIG_CONFIG=${sdkconfig}"
         "IDF_TARGET=${idf_target}"
+        "IDF_TOOLCHAIN=${idf_toolchain}"
         "IDF_ENV_FPGA=${idf_env_fpga}"
         ${MENUCONFIG_CMD} ${root_kconfig}
         USES_TERMINAL
         # additional run of kconfgen esures that the deprecated options will be inserted into sdkconfig (for backward
         # compatibility)
         COMMAND ${kconfgen_basecommand}
         --env "IDF_TARGET=${idf_target}"
+        --env "IDF_TOOLCHAIN=${idf_toolchain}"
         --env "IDF_ENV_FPGA=${idf_env_fpga}"
         --output config ${sdkconfig}
         )

tools/cmake/toolchain-clang-esp32h4.cmake

@@ -0,0 +1,32 @@
+include($ENV{IDF_PATH}/tools/cmake/utilities.cmake)
+
+set(CMAKE_SYSTEM_NAME Generic)
+
+set(CMAKE_C_COMPILER clang)
+set(CMAKE_CXX_COMPILER clang++)
+set(CMAKE_ASM_COMPILER clang)
+
+set(CMAKE_AR llvm-ar)
+set(CMAKE_RANLIB llvm-ranlib)
+set(CMAKE_OBJDUMP riscv32-esp-elf-objdump)
+
+remove_duplicated_flags("--target=riscv32-esp-elf -march=rv32imc -mabi=ilp32 \
+                        ${CMAKE_C_FLAGS}"
+                        UNIQ_CMAKE_C_FLAGS)
+set(CMAKE_C_FLAGS "${UNIQ_CMAKE_C_FLAGS}"
+    CACHE STRING "C Compiler Base Flags"
+    FORCE)
+
+remove_duplicated_flags("--target=riscv32-esp-elf -march=rv32imc -mabi=ilp32 \
+                        ${CMAKE_CXX_FLAGS}"
+                        UNIQ_CMAKE_CXX_FLAGS)
+set(CMAKE_CXX_FLAGS "${UNIQ_CMAKE_CXX_FLAGS}"
+    CACHE STRING "C++ Compiler Base Flags"
+    FORCE)
+
+remove_duplicated_flags("--target=riscv32-esp-elf -march=rv32imc -mabi=ilp32 \
+                        ${CMAKE_ASM_FLAGS}"
+                        UNIQ_CMAKE_ASM_FLAGS)
+set(CMAKE_ASM_FLAGS "${UNIQ_CMAKE_ASM_FLAGS}"
+    CACHE STRING "Assembler Base Flags"
+    FORCE)

tools/kconfig_new/config.env.in

@@ -3,6 +3,7 @@
     "COMPONENT_KCONFIGS_PROJBUILD": "${kconfig_projbuilds}",
     "COMPONENT_SDKCONFIG_RENAMES": "${sdkconfig_renames}",
     "IDF_TARGET": "${idf_target}",
+    "IDF_TOOLCHAIN": "${idf_toolchain}",
     "IDF_ENV_FPGA": "${idf_env_fpga}",
     "IDF_PATH": "${idf_path}",
     "COMPONENT_KCONFIGS_SOURCE_FILE": "${kconfigs_path}",

tools/test_apps/system/cxx_pthread_bluetooth/sdkconfig.ci.clang_libclang_rt

@@ -0,0 +1 @@
+CONFIG_COMPILER_RT_LIB_CLANGRT=y

tools/test_apps/system/cxx_pthread_bluetooth/sdkconfig.ci.clang_libgcc

@@ -0,0 +1 @@
+CONFIG_COMPILER_RT_LIB_GCCLIB=y