WIP remove autoconf.h

Signed-off-by: Axel Heider <[email protected]>

CHANGES.md

@@ -259,6 +259,7 @@ description indicates whether it is SOURCE-COMPATIBLE, BINARY-COMPATIBLE, or BRE
 * General minor build system improvements and clean-up
 * Set up automated tests for CI and GitHub pull requests on seL4
 * Add vulnerability disclosure policy
+* Removed autoconf.h for kernel and libsel4.
 
 ### Upgrade Notes
 

CMakeLists.txt

@@ -350,30 +350,16 @@ include_directories(
 #
 
 include_directories($<TARGET_PROPERTY:kernel_Config,INTERFACE_INCLUDE_DIRECTORIES>)
-# The kernel expects to be able to include an 'autoconf.h' file at the moment.
-# So lets generate one for it to use
-# TODO: use the kernel_Config directly
-generate_autoconf(kernel_autoconf "kernel")
-include_directories($<TARGET_PROPERTY:kernel_autoconf,INTERFACE_INCLUDE_DIRECTORIES>)
 
-# Target for the config / autoconf headers. This is what all the other generated headers
+# Target for the config headers. This is what all the other generated headers
 # can depend upon
-add_custom_target(
-    kernel_config_headers
-    DEPENDS
-        kernel_autoconf_Gen
-        kernel_autoconf
-        kernel_Config
-        kernel_Gen
-)
+add_custom_target(kernel_config_headers DEPENDS kernel_Config kernel_Gen)
 
-# Target for all generated headers. We start with just all the config / autoconf headers
+# Target for all generated headers. We start with just all the config headers
 add_custom_target(kernel_headers DEPENDS kernel_config_headers)
 
 # Build up a list of generated files. needed for dependencies in custom commands
-get_generated_files(gen_files_list kernel_autoconf_Gen)
-get_generated_files(gen_files2 kernel_Gen)
-list(APPEND gen_files_list "${gen_files2}")
+get_generated_files(gen_files_list kernel_Gen)
 
 #
 # C source generation
@@ -673,7 +659,7 @@ add_executable(kernel.elf EXCLUDE_FROM_ALL ${asm_sources} kernel_all.c)
 target_include_directories(kernel.elf PRIVATE ${config_dir})
 target_include_directories(kernel.elf PRIVATE include)
 target_include_directories(kernel.elf PRIVATE "${CMAKE_CURRENT_BINARY_DIR}/generated")
-target_link_libraries(kernel.elf PRIVATE kernel_Config kernel_autoconf)
+target_link_libraries(kernel.elf PRIVATE kernel_Config)
 set_property(TARGET kernel.elf APPEND_STRING PROPERTY LINK_FLAGS " -Wl,-T ${linker_lds_path} ")
 set_target_properties(kernel.elf PROPERTIES LINK_DEPENDS "${linker_lds_path}")
 add_dependencies(kernel.elf circular_includes)
@@ -711,10 +697,9 @@ if("${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
             "${CMAKE_CURRENT_BINARY_DIR}/libsel4/include/"
             "${CMAKE_CURRENT_BINARY_DIR}/libsel4/arch_include/${KernelArch}/"
             "${CMAKE_CURRENT_BINARY_DIR}/libsel4/sel4_arch_include/${KernelSel4Arch}/"
-            # The following directories install the autoconf headers
+            # The following directories install the configuration headers
             "${CMAKE_CURRENT_BINARY_DIR}/gen_config/"
             "${CMAKE_CURRENT_BINARY_DIR}/libsel4/gen_config/"
-            "${CMAKE_CURRENT_BINARY_DIR}/libsel4/autoconf/"
         DESTINATION libsel4/include
         FILES_MATCHING
         PATTERN "*.h"

include/sel4/gen_config.h

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2024, Codasip GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#pragma once
+
+/*
+ * This file exists, because the kernel includes the libsel4 headers, which
+ * need the header file 'sel4/gen_config.h' with the libsel4 configuration. When
+ * compiling the kernel, the libsel4 configuration has not been created yet, so
+ * we provide a dummy file here. This is fine because nothing in the libsel4
+ * configuration is relevant for the kernel.
+ */

libsel4/CMakeLists.txt

@@ -51,9 +51,6 @@ RequireFile(SYSCALL_STUB_GEN_PATH syscall_stub_gen.py PATHS tools)
 
 add_config_library(sel4 "${configure_string}")
 
-# Currently we use autoconf.h, so generate one of those
-generate_autoconf(sel4_autoconf "kernel;sel4")
-
 gen_invocation_header(
     OUTPUT "include/sel4/invocation.h"
     XML "include/interfaces/object-api.xml"
@@ -83,16 +80,8 @@ set(
 )
 include_directories("${source_header_dirs}")
 
-# Add the include directory of autoconf.h to the cflags for the bitfield generation
-include_directories("$<TARGET_PROPERTY:sel4_autoconf,INTERFACE_INCLUDE_DIRECTORIES>")
-
 function(genbf target_prefix pbf_location bf_location header_output)
-    get_generated_files(gen_list sel4_autoconf_Gen)
-    cppfile(
-        "${pbf_location}" ${target_prefix}_pbf "${bf_location}"
-        EXTRA_FLAGS -P
-        EXTRA_DEPS sel4_autoconf_Gen ${gen_list}
-    )
+    cppfile("${pbf_location}" ${target_prefix}_pbf "${bf_location}" EXTRA_FLAGS -P)
     GenHBFTarget(
         "libsel4"
         ${target_prefix}_h
@@ -176,7 +165,7 @@ add_custom_target(
 )
 
 add_library(sel4 src/sel4_bootinfo.c)
-target_link_libraries(sel4 PRIVATE kernel_Config sel4_Config sel4_autoconf)
+target_link_libraries(sel4 PRIVATE kernel_Config sel4_Config)
 target_include_directories(
     sel4
     PUBLIC

libsel4/include/sel4/config.h

@@ -6,6 +6,8 @@
 
 #pragma once
 
-/* Compile-time configuration parameters. Might be set by the build system. */
+/* Kernel configuration */
+#include <kernel/gen_config.h>
 
-#include <autoconf.h>
+/* Libsel4 configuration */
+#include <sel4/gen_config.h>

tools/helpers.cmake

@@ -575,40 +575,6 @@ macro(get_generated_files output target)
     get_property(${output} TARGET ${target} PROPERTY GENERATED_FILES)
 endmacro(get_generated_files)
 
-# This rule tries to emulate an 'autoconf' header. autoconf generated headers
-# were previously used as configuration, so this rule provides a way for previous
-# applications and libraries to build without modification. The config_list
-# is a list of 'prefix' values that have been passed to add_config_library
-# This generates a library with ${targetname} that when linked against
-# will allow code to simply #include <autoconf.h>
-function(generate_autoconf targetname config_list)
-    set(link_list "")
-    set(gen_list "")
-    set(config_header_contents "\n#pragma once\n\n")
-    foreach(config IN LISTS config_list)
-        list(APPEND link_list "${config}_Config")
-        get_generated_files(gens ${config}_Gen)
-        list(APPEND gen_list ${gens})
-        string(APPEND config_header_contents "#include <${config}/gen_config.h>\n")
-    endforeach()
-    set(config_dir "${CMAKE_CURRENT_BINARY_DIR}/autoconf")
-    set(config_file "${config_dir}/autoconf.h")
-
-    file(GENERATE OUTPUT "${config_file}" CONTENT "${config_header_contents}")
-    add_custom_target(${targetname}_Gen DEPENDS "${config_file}" ${gen_list})
-    add_library(${targetname} INTERFACE)
-    target_link_libraries(${targetname} INTERFACE ${link_list})
-    target_include_directories(${targetname} INTERFACE "${config_dir}")
-    add_dependencies(${targetname} ${targetname}_Gen ${config_file} ${gen_list})
-    # Set our GENERATED_FILES property to include the GENERATED_FILES of all of our input
-    # configurations, as well as the files we generated
-    set_property(
-        TARGET ${targetname}_Gen
-        APPEND
-        PROPERTY GENERATED_FILES "${config_file}" ${gen_list}
-    )
-endfunction(generate_autoconf)
-
 # Macro that allows for appending to a specified list only if all the supplied conditions are true
 macro(list_append_if list dep)
     set(list_append_local_list ${${list}})