http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54584
--- Comment #1 from Larry Baker <baker at usgs dot gov> 2012-09-15 00:39:14 UTC
---
I found that the -msep-data link would succeed if program section
.tm_clone_table has a non-zero length.
I changed __JCR_LIST__[] and __TMC_LIST__[] to __JCR_LIST__[1] and
__TMC_LIST__[1], respectively, in
gcc-4.7-20120908/libgcc/crtstuff.c.
The program sections in the original crtbegin.o have 0 length for program
section .tm_clone_table:
# freescale-coldfire-2011.09/bin/m68k-uclinux-objdump -h
cross-gcc-4.7-20120908/gcc/msep-data/crtbegin.o
cross-gcc-4.7-20120908/gcc/msep-data/crtbegin.o: file format elf32-m68k
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00000136 00000000 00000000 00000034 2**2
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
1 .data 00000004 00000000 00000000 0000016c 2**2
CONTENTS, ALLOC, LOAD, DATA
2 .bss 0000001e 00000000 00000000 00000170 2**2
ALLOC
3 .ctors 00000004 00000000 00000000 00000170 2**2
CONTENTS, ALLOC, LOAD, DATA
4 .dtors 00000004 00000000 00000000 00000174 2**2
CONTENTS, ALLOC, LOAD, DATA
5 .eh_frame 00000000 00000000 00000000 00000178 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
6 .jcr 00000000 00000000 00000000 00000178 2**2
CONTENTS, ALLOC, LOAD, DATA
7 .tm_clone_table 00000000 00000000 00000000 00000178 2**2
CONTENTS, ALLOC, LOAD, DATA
8 .fini 00000006 00000000 00000000 00000178 2**0
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
9 .init 00000006 00000000 00000000 0000017e 2**0
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
10 .comment 00000028 00000000 00000000 00000184 2**0
CONTENTS, READONLY
11 .note.GNU-stack 00000000 00000000 00000000 000001ac 2**0
CONTENTS, READONLY
The new one has length 4:
# freescale-coldfire-2011.09/bin/m68k-uclinux-objdump -h
cross-gcc-4.7-20120908/gcc/msep-data/crtbegin.o
cross-gcc-4.7-20120908/gcc/msep-data/crtbegin.o: file format elf32-m68k
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00000136 00000000 00000000 00000034 2**2
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
1 .data 00000004 00000000 00000000 0000016c 2**2
CONTENTS, ALLOC, LOAD, DATA
2 .bss 0000001e 00000000 00000000 00000170 2**2
ALLOC
3 .ctors 00000004 00000000 00000000 00000170 2**2
CONTENTS, ALLOC, LOAD, DATA
4 .dtors 00000004 00000000 00000000 00000174 2**2
CONTENTS, ALLOC, LOAD, DATA
5 .eh_frame 00000000 00000000 00000000 00000178 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
6 .jcr 00000004 00000000 00000000 00000178 2**2
CONTENTS, ALLOC, LOAD, DATA
7 .tm_clone_table 00000004 00000000 00000000 0000017c 2**2
CONTENTS, ALLOC, LOAD, DATA
8 .fini 00000006 00000000 00000000 00000180 2**0
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
9 .init 00000006 00000000 00000000 00000186 2**0
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
10 .comment 00000028 00000000 00000000 0000018c 2**0
CONTENTS, READONLY
11 .note.GNU-stack 00000000 00000000 00000000 000001b4 2**0
CONTENTS, READONLY
I do not know if this results in a correctly allocated or populated
.tm_clone_table. All I know is that the zero length allocation caused the link
failure. Is this due to the ALLOC attribute with 0 length? Is this a
consequence of __attribute__((used))?
