xref: /netbsd-src/tests/usr.bin/xlint/lint1/platform_ilp32_long.c (revision d16b7486a53dcb8072b60ec6fcb4373a2d0c27b7)
1 /*	$NetBSD: platform_ilp32_long.c,v 1.4 2023/07/08 15:26:25 rillig Exp $	*/
2 # 3 "platform_ilp32_long.c"
3 
4 /*
5  * Test features that only apply to platforms that have 32-bit int, long and
6  * pointer types and where size_t is unsigned long, not unsigned int.
7  *
8  * On these platforms, in portable mode (-p), the type 'int' is in some cases
9  * assumed to be only 24 bits wide, in order to detect conversions from
10  * 'long' (or more probably 'size_t') to 'int', which can lose accuracy.
11  */
12 
13 /* lint1-only-if: ilp32 long */
14 /* lint1-extra-flags: -c -h -a -p -b -r -z -X 351 */
15 
16 int s32;
17 unsigned int u32;
18 long sl32;
19 unsigned long ul32;
20 
21 void
22 convert_between_int_and_long(void)
23 {
24 	/*
25 	 * The '-p' option enables checks that apply independently of the
26 	 * current platform, assuming that 'long' is always wider than 'int'.
27 	 * This assumption, when applied on its own, leads to wrong warnings
28 	 * that a 32-bit 'long' may lose accuracy when converted to a 32-bit
29 	 * 'int'.
30 	 *
31 	 * To avoid these, take a look at the actually possible values of the
32 	 * right-hand side, and if they fit in the left-hand side, don't warn.
33 	 */
34 	s32 = sl32;
35 	sl32 = s32;
36 	u32 = ul32;
37 	ul32 = u32;
38 }
39