[Bug target/82411] const is not always read-only

["segher at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82411

--- Comment #8 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Author: segher
Date: Tue Mar 27 23:13:02 2018
New Revision: 258907

URL: https://gcc.gnu.org/viewcvs?rev=258907&root=gcc&view=rev
Log:
rs6000: -mreadonly-in-sdata (PR82411)

This adds a new option -mreadonly-in-sdata (on by default) that
controls whether readonly data can be put in sdata.  (For EABI this
does nothing, readonly data is put in sdata2 as usual).


        Backport from mainline
        2018-03-08  Segher Boessenkool  <segher@kernel.crashing.org>

        PR target/82411
        * config/rs6000/rs6000.c (rs6000_elf_in_small_data_p): Don't put
        readonly data in sdata, if that is disabled.
        * config/rs6000/sysv4.opt (mreadonly-in-sdata): New option.
        * doc/invoke.texi (RS/6000 and PowerPC Options): Document
        -mreadonly-in-sdata option.


        Backport from mainline
        2018-03-08  Segher Boessenkool  <segher@kernel.crashing.org>

        PR target/82411
        * gcc.target/powerpc/ppc-sdata-2.c: Skip if -mno-readonly-in-sdata.

Modified:
    branches/gcc-7-branch/gcc/ChangeLog
    branches/gcc-7-branch/gcc/config/rs6000/rs6000.c
    branches/gcc-7-branch/gcc/config/rs6000/sysv4.opt
    branches/gcc-7-branch/gcc/doc/invoke.texi
    branches/gcc-7-branch/gcc/testsuite/ChangeLog
    branches/gcc-7-branch/gcc/testsuite/gcc.target/powerpc/ppc-sdata-2.c