After commit "tccelf: unify SHT_NOTE sections" openbsd and freebsd do
not work anymore.
I debugged the problem and found that if I disable the GNU_RELRO section
the problem disappears.
If I compile examples/ex2.c with tcc and use "readelf -e -W a.out" on
openbsd I get:
Program Headers:
Type Offset VirtAddr PhysAddr FileSiz MemSiz
Flg Align
PHDR 0x000040 0x0000000000400040 0x0000000000400040
0x0001c0 0x0001c0 R 0x4
INTERP 0x000940 0x0000000000400940 0x0000000000400940
0x000013 0x000013 R 0x1
[Requesting program interpreter: /usr/libexec/ld.so]
LOAD 0x000000 0x0000000000400000 0x0000000000400000
0x000f21 0x000f21 R 0x1000
LOAD 0x000f30 0x0000000000401f30 0x0000000000401f30
0x000a0c 0x000a0c R E 0x1000
LOAD 0x001940 0x0000000000403940 0x0000000000403940
0x000218 0x00040c RW 0x1000
DYNAMIC 0x001940 0x0000000000403940 0x0000000000403940
0x000140 0x000140 RW 0x8
NOTE 0x000958 0x0000000000400958 0x0000000000400958
0x000078 0x000078 R 0x8
GNU_RELRO 0x001940 0x0000000000403940 0x0000000000403940
0x0001c8 0x0001c8 RW 0x1
Section to Segment mapping:
Segment Sections...
00
01 .interp
02 .interp .note.gnu.property .note.openbsd.ident .dynsym
.dynstr .hash .gnu.hash .rela.got .rela.plt .eh_frame .data.ro
03 .init .fini .plt .text
04 .dynamic .got .openbsd.randomdata.retguard.1205 .jcr .ctors
.dtors .openbsd.randomdata .openbsd.randomdata.retguard.2473
.openbsd.randomdata.retguard.1471 .openbsd.randomdata.retguard.1773 .bss
05 .dynamic
06 .note.gnu.property .note.openbsd.ident
07 .dynamic .got
The ".bss" is in the same LOAD section as the " .dynamic .got" section.
The problem is that openbsd and freebsd set the whole LOAD section to RO.
This means that the ".bss" section becomes RO and the first write to
".bss" crashes.
If I revert the commit the ".dynamic .got" sections are in a seperate
LOAD section.
Herman
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