v: fix remaining macOS SDK and Linux cross-build CI failures (#31103)

vlib/v/driver/c_compiler_flags_test.v

@@ -418,6 +418,81 @@ fn test_linux_cross_link_flags_unwrap_clang_driver_flags() {
 	]
 }
 
+fn test_linux_cross_compiles_native_sources_in_flag_plan() {
+	$if windows {
+		return
+	}
+	root := os.join_path(os.vtmp_dir(), 'v3_linux_cross_sources_${os.getpid()}')
+	os.rmdir_all(root) or {}
+	os.mkdir_all(root)!
+	defer {
+		os.rmdir_all(root) or {}
+	}
+	build_dir := os.join_path(root, 'build space')
+	os.mkdir_all(build_dir)!
+	for source in ['before.c', 'objc.m', 'main.c', 'upper.C', 'side car.mm', 'side.cpp', 'signal.c',
+		'forced.c', 'retained.o'] {
+		os.write_file(os.join_path(build_dir, source), '')!
+	}
+	compiler := write_windows_prod_test_tool(os.join_path(root, 'fake-cc'), r'
+set -eu
+source=""
+output=""
+language=""
+while [ "$#" -gt 0 ]; do
+	case "$1" in
+		-o) output="$2"; shift 2 ;;
+		-x) language="$2"; shift 2 ;;
+		-I|-D|-include|-target) shift 2 ;;
+		-*) shift ;;
+		*) [ -z "$source" ] || exit 91; source="$1"; shift ;;
+	esac
+done
+[ -f "$source" ] && [ -n "$output" ] || exit 92
+printf "%s|%s\n" "$source" "$language" >> compiled-sources.log
+printf "%s|%s\n" "$source" "$language" > "$output"
+')
+	write_windows_prod_test_tool(os.join_path(root, 'sysroot', 'ld.lld'), r'
+set -eu
+output=""
+objects=0
+retained=0
+while [ "$#" -gt 0 ]; do
+	case "$1" in
+		-o) output="$2"; shift 2 ;;
+		-L|-l|-m|-dynamic-linker) shift 2 ;;
+		linux_cross_*.o)
+			[ -f "$1" ] || exit 93
+			IFS= read -r identity < "$1"
+			printf "%s\n" "$identity" >> linked-sources.log
+			objects=$((objects + 1))
+			shift ;;
+		retained.o) [ -f "$1" ] || exit 94; retained=1; shift ;;
+		*.c|*.C|*.cpp|*.m|*.mm|*.S) exit 95 ;;
+		*) shift ;;
+	esac
+done
+[ "$objects" -eq 7 ] && [ "$retained" -eq 1 ] && [ -n "$output" ] || exit 96
+: > "$output"
+')
+	// Language selectors span argument sections; option operands are never inputs.
+	plan := V3CCompilerFlagPlan{
+		before_inputs: ['-I', 'includes.c', '-D', '-x', '-include', 'forced.c', '-x', 'c', 'before.c',
+			'-xobjective-c']
+		after_inputs:  ['-D', 'NOT_A_SOURCE.cpp', '-x', 'objective-c++', 'side car.mm', '-x', 'none',
+			'side.cpp', '-x', 'c', 'signal.c', '-x', 'none', '-L', 'lib.c', '-l', 'dep', 'retained.o']
+	}
+	result := compile_v3_macos_linux_cross(compiler, &plan, ['objc.m', '-x', 'none', 'main.c',
+		'upper.C'], os.join_path(root, 'sysroot'), root,
+		build_dir, 'program', false, false)
+	assert result.exit_code == 0, result.output
+	expected := ['before.c|c', 'objc.m|objective-c', 'main.c|', 'upper.C|', 'side car.mm|objective-c++',
+		'side.cpp|', 'signal.c|c']
+	assert os.read_file(os.join_path(build_dir, 'compiled-sources.log'))!.split_into_lines() == expected
+	assert os.read_file(os.join_path(build_dir, 'linked-sources.log'))!.split_into_lines() == expected
+	assert os.is_file(os.join_path(build_dir, 'program'))
+}
+
 fn test_v3_implicit_tcc_uses_platform_compiler_for_non_c_objects() {
 	implicit_tcc := os.join_path(os.temp_dir(), 'bin', 'tcc')
 	assert c_source_object_compiler('', implicit_tcc, true, 'linux') == implicit_tcc

vlib/v/driver/driver.v

@@ -3117,22 +3117,44 @@ fn v3_linux_cross_source_input(input string) bool {
 }
 
 fn compile_v3_macos_linux_cross(c_compiler string, c_flag_plan &V3CCompilerFlagPlan, compiler_inputs []string, sysroot string, vroot string, build_dir string, output_name string, show_command bool, is_shared bool) os.Result {
-	mut compile_flags := c_object_compile_flags(c_flag_plan.before_inputs)
-	compile_flags << c_object_compile_flags(c_flag_plan.after_inputs)
-	compile_flags << c_object_compile_flags(compiler_inputs)
+	mut inputs := c_flag_plan.before_inputs.clone()
+	inputs << compiler_inputs
+	inputs << c_flag_plan.after_inputs
+	mut compile_flags := c_object_compile_flags(inputs)
 	if '-fPIC' !in compile_flags {
 		compile_flags << '-fPIC'
 	}
 	mut objects := []string{}
 	mut source_index := 0
-	for raw_input in compiler_inputs {
-		input := raw_input.trim(' \t\r\n"\'')
-		if !v3_linux_cross_source_input(input) {
+	mut language := ''
+	mut i := 0
+	for i < inputs.len {
+		input := inputs[i].trim(' \t\r\n"\'')
+		if input == '-x' {
+			language = if i + 1 < inputs.len { inputs[i + 1].trim_space() } else { '' }
+			i += 2
+			continue
+		}
+		joined_language := c_joined_source_language(input)
+		if joined_language.len > 0 {
+			language = joined_language
+			i++
+			continue
+		}
+		if c_flag_consumes_next_operand(input) {
+			i += 2
+			continue
+		}
+		i++
+		if input.starts_with('-') || !v3_linux_cross_source_input(input) {
 			continue
 		}
 		object_name := 'linux_cross_${source_index}.o'
 		source_index++
 		mut args := compile_flags.clone()
+		if language !in ['', 'none'] {
+			args << ['-x', language]
+		}
 		args << ['-c', '-o', object_name, input]
 		if show_command {
 			println('  > ${cmdexec.display(c_compiler, args)}')
@@ -3143,7 +3165,7 @@ fn compile_v3_macos_linux_cross(c_compiler string, c_flag_plan &V3CCompilerFlagP
 		}
 		objects << object_name
 	}
-	if objects.len == 0 && !compiler_inputs.any(c_flag_is_object_file(it.trim_space())) {
+	if objects.len == 0 && !c_link_input_indices(inputs).any(c_flag_is_object_file(inputs[it].trim_space())) {
 		return os.Result{
 			exit_code: 1
 			output:    'Linux cross compilation has no C source or object input'
@@ -3183,8 +3205,7 @@ fn compile_v3_macos_linux_cross(c_compiler string, c_flag_plan &V3CCompilerFlagP
 	}
 	linker_args << os.join_path(sysroot, 'crti.o')
 	linker_args << objects
-	linker_args << v3_linux_cross_link_flags(compiler_inputs)
-	linker_args << v3_linux_cross_link_flags(c_flag_plan.after_inputs)
+	linker_args << v3_linux_cross_link_flags(inputs)
 	linker_args << ['-lc', '-lcrypto', '-lssl', '-lpthread', os.join_path(sysroot, 'crtn.o'), '-lm',
 		'-ldl']
 	linker := os.join_path(sysroot, 'ld.lld')

vlib/v/gen/c/darwin_x64_symbols_test.v

@@ -121,7 +121,7 @@ fn test_x86_64_sdk_symbols_are_only_written_for_macos_and_portable_c() {
 }
 
 // The table is checked against the installed SDK: its headers have to link every
-// listed function to the listed symbol on x86_64.
+// available function to the listed symbol on x86_64.
 fn test_x86_64_sdk_symbol_table_matches_the_installed_sdk() {
 	$if !macos {
 		return
@@ -129,13 +129,30 @@ fn test_x86_64_sdk_symbol_table_matches_the_installed_sdk() {
 	dir := os.join_path(os.vtmp_dir(), 'darwin_x64_sdk_${os.getpid()}')
 	os.mkdir_all(dir)!
 	defer { os.rmdir_all(dir) or {} }
+	// Query the compiler's SDK, which may differ from the running macOS version.
+	version_source := os.join_path(dir, 'sdk_version.c')
+	os.write_file(version_source, '#include <AvailabilityMacros.h>\nV_DARWIN_SDK_MAX __MAC_OS_X_VERSION_MAX_ALLOWED\n')!
+	version := cmdexec.run('cc', ['-arch', 'x86_64', '-E', '-P', version_source])
+	assert version.exit_code == 0, version.output
+	assert version.output.contains('V_DARWIN_SDK_MAX '), version.output
+	sdk_version := version.output.all_after('V_DARWIN_SDK_MAX ').trim_space().int()
+	assert sdk_version > 0, version.output
+	mut sdk_symbols := map[string]string{}
+	for name, symbol in c_darwin_x64_sdk_symbols {
+		// These dirent APIs were added in the macOS 26.4 SDK. Older SDKs still
+		// validate every other entry instead of failing on undeclared names.
+		if sdk_version < 260400 && name in ['fdscandir', 'fdscandir_b', 'scandirat', 'scandirat_b'] {
+			continue
+		}
+		sdk_symbols[name] = symbol
+	}
 	mut code := ''
 	for header in ['dirent.h', 'fts.h', 'ftw.h', 'glob.h', 'stdlib.h', 'syslog.h', 'unistd.h',
 		'sys/mount.h', 'sys/select.h', 'sys/stat.h'] {
 		code += '#include <${header}>\n'
 	}
 	code += 'void* v_sdk_symbols[] = {\n'
-	for name, _ in c_darwin_x64_sdk_symbols {
+	for name, _ in sdk_symbols {
 		code += '\t(void*)&${name},\n'
 	}
 	code += '};\n'
@@ -145,7 +162,7 @@ fn test_x86_64_sdk_symbol_table_matches_the_installed_sdk() {
 	build := cmdexec.run('cc', ['-arch', 'x86_64', '-w', '-c', '-o', object, source])
 	assert build.exit_code == 0, build.output
 	symbols := undefined_symbols(object)
-	for name, symbol in c_darwin_x64_sdk_symbols {
+	for name, symbol in sdk_symbols {
 		assert symbol in symbols, '${name}: ${symbols}'
 	}
 }