xref: /rk3399_rockchip-uboot/arch/arm/lib/sections.c (revision df84502edffd1da48588a212b402602f032ed53d)
1*df84502eSAlbert ARIBAUD /*
2*df84502eSAlbert ARIBAUD  * Copyright 2013 Albert ARIBAUD <albert.u.boot@aribaud.net>
3*df84502eSAlbert ARIBAUD  *
4*df84502eSAlbert ARIBAUD  * See file CREDITS for list of people who contributed to this
5*df84502eSAlbert ARIBAUD  * project.
6*df84502eSAlbert ARIBAUD  *
7*df84502eSAlbert ARIBAUD  * This program is free software; you can redistribute it and/or
8*df84502eSAlbert ARIBAUD  * modify it under the terms of the GNU General Public License as
9*df84502eSAlbert ARIBAUD  * published by the Free Software Foundation; either version 2 of
10*df84502eSAlbert ARIBAUD  * the License, or (at your option) any later version.
11*df84502eSAlbert ARIBAUD  *
12*df84502eSAlbert ARIBAUD  * This program is distributed in the hope that it will be useful,
13*df84502eSAlbert ARIBAUD  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14*df84502eSAlbert ARIBAUD  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15*df84502eSAlbert ARIBAUD  * GNU General Public License for more details.
16*df84502eSAlbert ARIBAUD  *
17*df84502eSAlbert ARIBAUD  * You should have received a copy of the GNU General Public License
18*df84502eSAlbert ARIBAUD  * along with this program; if not, write to the Free Software
19*df84502eSAlbert ARIBAUD  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
20*df84502eSAlbert ARIBAUD  * MA 02111-1307 USA
21*df84502eSAlbert ARIBAUD  */
22*df84502eSAlbert ARIBAUD 
23*df84502eSAlbert ARIBAUD /**
24*df84502eSAlbert ARIBAUD  * These two symbols are declared in a C file so that the linker
25*df84502eSAlbert ARIBAUD  * uses R_ARM_RELATIVE relocation, rather than the R_ARM_ABS32 one
26*df84502eSAlbert ARIBAUD  * it would use if the symbols were defined in the linker file.
27*df84502eSAlbert ARIBAUD  * Using only R_ARM_RELATIVE relocation ensures that references to
28*df84502eSAlbert ARIBAUD  * the symbols are correct after as well as before relocation.
29*df84502eSAlbert ARIBAUD  *
30*df84502eSAlbert ARIBAUD  * We need a 0-byte-size type for these symbols, and the compiler
31*df84502eSAlbert ARIBAUD  * does not allow defining objects of C type 'void'. Using an empty
32*df84502eSAlbert ARIBAUD  * struct is allowed by the compiler, but causes gcc versions 4.4 and
33*df84502eSAlbert ARIBAUD  * below to complain about aliasing. Therefore we use the next best
34*df84502eSAlbert ARIBAUD  * thing: zero-sized arrays, which are both 0-byte-size and exempt from
35*df84502eSAlbert ARIBAUD  * aliasing warnings.
36*df84502eSAlbert ARIBAUD  */
37*df84502eSAlbert ARIBAUD 
38*df84502eSAlbert ARIBAUD char __bss_start[0] __attribute__((section(".__bss_start")));
39*df84502eSAlbert ARIBAUD char __bss_end[0] __attribute__((section(".__bss_end")));
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