http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60158
Bug ID: 60158
Summary: powerpc: usage of the .data.rel.ro.local section
Product: gcc
Version: 4.8.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: jal2 at gmx dot de
This bug may concern the gcc documentation on section usage only.
Crosscompiling "Das U-Boot" with gcc 4.8.2 for powerpc with
-fpic -mrelocatable, some addresses are put into a section .data.rel.ro.local,
e.g. the address of "qwerty" from
printf("%p\n", "qwerty");
There is no corresponding entry in the .fixup section.
As "Das U-Boot" relocates itself to RAM using .got2/.got and .fixup sections
only, how shall the section .data.rel.ro.local be handled?
Currently it contains addresses only, but this may depend on the source code.
I put .data.rel.ro.local into the GOT which solved my problem, but I'm not sure
if this is the intention of the gcc developers.
I've tried gcc 4.7.3 which put the address of "qwerty" into the GOT directly,
i.e. there was no .data.rel.ro.local section and the string address was
accessed with one redirection less.
details:
- gcc version: powerpc-softfloat-linux-gnuspe-gcc (Gentoo 4.8.2 p1.3r1,
pie-0.5.8r1) 4.8.2
- gcc command line (some -I removed):
-g -gdwarf-2 -Os -fpic -mrelocatable \
-meabi \
-D__KERNEL__ -DCONFIG_SYS_TEXT_BASE=0xef770000 \
-fno-builtin -ffreestanding \
-isystem /usr/lib/gcc/powerpc-softfloat-linux-gnuspe/4.8.1/include \
-nostdinc -pipe -DCONFIG_PPC -D__powerpc__ -ffixed-r2 -Wa,-me500 \
-msoft-float -mno-string -mspe=yes -mno-spe -Wall -Wstrict-prototypes \
-fno-stack-protector -Wno-format-nonliteral -Wno-format-security \
-fstack-usage"
