[3.5] writable .gcc_except_table for mips[64]
To match gcc behavior and avoid ld warning like this on project using
prebuilts/ndk 's libc++
.../ld: warning: creating a DT_TEXTREL in a shared object.
(*1)
switch_to_exception_section (const char * ARG_UNUSED (fnname))
{
....
if (EH_TABLES_CAN_BE_READ_ONLY)
{
int tt_format =
ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/1); # DW_EH_PE_indirect which is 0x80
flags = ((! flag_pic
|| ((tt_format & 0x70) != DW_EH_PE_absptr/*0x00*/
&& (tt_format & 0x70) != DW_EH_PE_aligned/*0x50*/))
? 0 : SECTION_WRITE);
}
else
flags = SECTION_WRITE;
...
}
Note that PIC is the default for Android toolchain. For MIPS,
ASM_PREFERRED_EH_DATA_FORMAT returns 0x80 and fails condition
about "DW_EH_PE_absptr"
The exact reason why .gcc_except_table contain reloc (and causes
ld warning turns in to error thanks to -Wl,--fatal-warnings when it
isn't writable thus requires load-time fixup in read-only section
and security concern) isn't well understood, though
Change-Id: I5e05ee052af48f06e8c4e3a01c317f4010a2ddaf
1 file changed
