xref: /openbmc/u-boot/arch/arm/lib/sections.c (revision ac1058fd)
1 /*
2  * Copyright 2013 Albert ARIBAUD <albert.u.boot@aribaud.net>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 /**
8  * These two symbols are declared in a C file so that the linker
9  * uses R_ARM_RELATIVE relocation, rather than the R_ARM_ABS32 one
10  * it would use if the symbols were defined in the linker file.
11  * Using only R_ARM_RELATIVE relocation ensures that references to
12  * the symbols are correct after as well as before relocation.
13  *
14  * We need a 0-byte-size type for these symbols, and the compiler
15  * does not allow defining objects of C type 'void'. Using an empty
16  * struct is allowed by the compiler, but causes gcc versions 4.4 and
17  * below to complain about aliasing. Therefore we use the next best
18  * thing: zero-sized arrays, which are both 0-byte-size and exempt from
19  * aliasing warnings.
20  */
21 
22 char __bss_start[0] __attribute__((section(".__bss_start")));
23 char __bss_end[0] __attribute__((section(".__bss_end")));
24 char __image_copy_start[0] __attribute__((section(".__image_copy_start")));
25 char __image_copy_end[0] __attribute__((section(".__image_copy_end")));
26 char __rel_dyn_start[0] __attribute__((section(".__rel_dyn_start")));
27 char __rel_dyn_end[0] __attribute__((section(".__rel_dyn_end")));
28 char _end[0] __attribute__((section(".__end")));
29