Merge pull request managarm#1122 from qookei/freestnd-hdrs-option

meson: Add option to prevent using freestnd-c{,xx}-hdrs

README.md

@@ -32,6 +32,7 @@ The following custom meson options are accepted, in addition to the [built-in op
 - `build_tests`: Build the test suite (see below).
 - `disable_x_option`: Disable `x` component of mlibc functionality. See `meson_options.txt` for a full list of possible values for `x`. This may be used to e.g disable POSIX and glibc extensions.
 - `linux_kernel_headers`: Allows for directing mlibc to installed linux headers. [These can be obtained easily](https://docs.kernel.org/kbuild/headers_install.html), placed in a directory and this option set to the corresponding path. This is required if the linux option is enabled, i.e. when the linux option is not disabled.
+- `use_freestnd_hdrs`: Use freestnd-c{,xx}-hdrs instead of looking for compiler headers. Useful if not using a compiler with the correct target triple.
 
 The type of library to be built (static, shared, or both) is controlled by meson's `default_library` option. Passing `-Ddefault_library=static` effectively disables the dynamic linker.
 

meson.build

@@ -43,17 +43,25 @@ internal_conf = configuration_data()
 mlibc_conf = configuration_data()
 
 if not headers_only
+	add_languages('c', 'cpp')
+	c_compiler = meson.get_compiler('c')
+	cpp_compiler = meson.get_compiler('cpp')
+
+	target_triple = run_command(c_compiler.cmd_array(), '-dumpmachine', check: true).stdout()
+	use_freestnd_hdrs = get_option('use_freestnd_hdrs').disable_auto_if(
+			target_triple.to_lower().contains('mlibc'))
+
 	freestnd_c_hdrs_dep = dependency(
 		'freestnd-c-hdrs-' + host_machine.cpu_family(),
-		required: false,
+		required: use_freestnd_hdrs,
 		fallback: ['freestnd-c-hdrs', 'freestnd_c_hdrs_dep'],
 	)
 	libc_deps += freestnd_c_hdrs_dep
 	rtld_deps += freestnd_c_hdrs_dep
 
 	freestnd_cxx_hdrs_dep = dependency(
 		'freestnd-cxx-hdrs-' + host_machine.cpu_family(),
-		required: false,
+		required: use_freestnd_hdrs,
 		fallback: ['freestnd-cxx-hdrs', 'freestnd_cxx_hdrs_dep'],
 	)
 	libc_deps += freestnd_cxx_hdrs_dep
@@ -67,10 +75,6 @@ if not headers_only
 	libc_deps += frigg_dep
 	rtld_deps += frigg_dep
 
-	add_languages('c', 'cpp')
-	c_compiler = meson.get_compiler('c')
-	cpp_compiler = meson.get_compiler('cpp')
-
 	add_project_arguments('-Wno-unused-function', '-D__MLIBC_BUILDING_MLIBC', language: ['c', 'cpp'])
 	add_project_arguments('-nostdinc', '-fno-builtin', '-ffreestanding', language: ['c', 'cpp'])
 	add_project_arguments('-Werror=misleading-indentation', language: ['c', 'cpp'])

meson_options.txt

@@ -15,3 +15,5 @@ option('linux_kernel_headers', type: 'string', value : '')
 option('default_library_paths', type: 'array', value: [])
 option('debug_allocator', type : 'boolean', value : false,
 	description : 'Enable the debug allocator, which uses mmap for every allocation and adds guard pages for each allocation')
+option('use_freestnd_hdrs', type : 'feature', value : 'auto',
+	description : 'Use freestnd-c{,xx}-hdrs instead of looking for compiler headers')