feat platform: optimize cross-compile by using try compile to determine types

Signed-off-by: John Sanpe <sanpeqf@gmail.com>

Author: pixclk

scripts/compare-type.c

@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright(c) 2023 John Sanpe <sanpeqf@gmail.com>
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+
+#if !defined(TYPE1) || !defined(TYPE2)
+# error "Undefine types"
+#endif
+
+#define typecheck(type, object) ({ \
+    type __dummy1; \
+    typeof(object) __dummy2; \
+    (void)(&__dummy1 == &__dummy2); \
+    1; \
+})
+
+int
+main(int argc, const char *argv[])
+{
+    typecheck(TYPE1, (TYPE2){0});
+    return 0;
+}

scripts/get-type.c

@@ -0,0 +1,42 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright(c) 2025 John Sanpe <sanpeqf@gmail.com>
+#
+
+function(compare_type result type1 type2)
+    message(DEBUG "Compare type: '${type1}' '${type2}'")
+    try_compile(
+        COMPILE_RESULT
+        ${CMAKE_CURRENT_BINARY_DIR}
+        ${CMAKE_CURRENT_LIST_DIR}/compare-type.c
+        COMPILE_DEFINITIONS "-Werror -Wcompare-distinct-pointer-types"
+        COMPILE_DEFINITIONS "-DTYPE1=${type1}"
+        COMPILE_DEFINITIONS "-DTYPE2=${type2}"
+        OUTPUT_VARIABLE OUTPUT
+    )
+    set(${result} ${COMPILE_RESULT} PARENT_SCOPE)
+endfunction()
+
+function(get_type result name default)
+    message(CHECK_START "Looking for type '${name}'")
+    set(candidates "int" "long" "long long" "char" "short")
+
+    foreach(walk IN LISTS candidates)
+        compare_type(compare "${name}" "${walk}")
+        if(NOT ${compare})
+            compare_type(compare "${name}" "unsigned ${walk}")
+        endif()
+
+        if(${compare})
+            set(type "${walk}")
+            message(CHECK_PASS "found '${walk}'")
+            break()
+        endif()
+    endforeach()
+
+    if(NOT type)
+        message(CHECK_FAIL "use default '${default}'")
+        set(type "${default}")
+    endif()
+    set(${result} "${type}" PARENT_SCOPE)
+endfunction()

scripts/get-type.cmake

@@ -3,29 +3,6 @@
 # Copyright(c) 2025 John Sanpe <sanpeqf@gmail.com>
 #
 
-if(HOST_C_COMPILER)
-    set(PRINT_TYPE_LINK "-static")
-endif()
-
-macro(print_type output name)
-    message(STATUS "Print type: " ${name})
-    try_run(
-        RUN_RESULT
-        COMPILE_RESULT
-        ${CMAKE_CURRENT_BINARY_DIR}
-        ${CMAKE_CURRENT_LIST_DIR}/get-type.c
-        COMPILE_DEFINITIONS "-Werror -DTYPE=${name}"
-        LINK_OPTIONS "${PRINT_TYPE_LINK}"
-        RUN_OUTPUT_VARIABLE ${output}
-        COMPILE_OUTPUT_VARIABLE COMPILE_OUTPUT
-    )
-    if ((NOT COMPILE_RESULT) OR (NOT RUN_RESULT EQUAL 0))
-        message("Compile output: ${COMPILE_OUTPUT}")
-        message("Run result: ${RUN_RESULT}")
-        message(FATAL_ERROR "Failed to retrieve the original type ${name}")
-    endif()
-endmacro()
-
 if(CMAKE_SYSTEM_NAME MATCHES "Linux|Android|Darwin|GNU")
     set(BFDEV_PORT_TYPE "posix")
 endif()
@@ -42,20 +19,7 @@ if(CMAKE_SYSTEM_NAME MATCHES "Generic")
     set(BFDEV_PORT_TYPE "generic")
 endif()
 
-if(BFDEV_PORT_TYPE STREQUAL "posix")
-    print_type(BFDEV_TYPE_ADDR "size_t")
-    print_type(BFDEV_TYPE_W64 "int64_t")
-    print_type(BFDEV_TYPE_MAX "intmax_t")
-endif()
-
-if(NOT BFDEV_TYPE_ADDR)
-    set(BFDEV_TYPE_ADDR "long")
-endif()
-
-if(NOT BFDEV_TYPE_W64)
-    set(BFDEV_TYPE_W64 "long long")
-endif()
-
-if(NOT BFDEV_TYPE_MAX)
-    set(BFDEV_TYPE_MAX "long long")
-endif()
+include(${CMAKE_CURRENT_LIST_DIR}/get-type.cmake)
+get_type(BFDEV_TYPE_ADDR "size_t" "long")
+get_type(BFDEV_TYPE_W64 "int64_t" "long long")
+get_type(BFDEV_TYPE_MAX "intmax_t" "long long")