[Bug lto/45729] -flto conflicts with -mthumb

[Bug lto/45729] -flto conflicts with -mthumb

[rafael.carre at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45729

Rafaël Carré <rafael.carre at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID

--- Comment #2 from Rafaël Carré <rafael.carre at gmail dot com> 2010-09-29 17:58:18 UTC ---
(In reply to comment #1)
> Can you retry without LTO so we can diagnose the interworking problems?

It works fine without LTO so I guess this bug can be closed

[Bug lto/45729] -flto conflicts with -mthumb

[andre.rosa at lge dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45729

Andre Goddard Rosa <andre.rosa at lge dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |andre.rosa at lge dot com

--- Comment #3 from Andre Goddard Rosa <andre.rosa at lge dot com> ---
Is LTO playing well with thumb as far as 4.8.3 is concerned or still not
supported?

Got the following when mixing "-mthumb" with "-flto=8 -fuse-linker-plugin":

| /tmp/ccQ4Z3ej.s: Assembler messages:
| /tmp/ccQ4Z3ej.s:21: Error: lo register required -- `str lr,[sp,#4]'
| /tmp/ccQ4Z3ej.s:31: Error: lo register required -- `str lr,[sp,#4]'
...
| /tmp/ccQ4Z3ej.s:1134: Error: lo register required -- `ldr lr,[sp,#0x38]'
| /tmp/ccQ4Z3ej.s:1158: Error: instruction not supported in Thumb16 mode --
`adds r3,#5'
| /tmp/ccQ4Z3ej.s:1173: Error: lo register required -- `ldr r10,[r1,#60]'
| /tmp/ccQ4Z3ej.s:1174: Error: lo register required -- `ldr r3,[r10,#0]'
| /tmp/ccQ4Z3ej.s:1186: Error: instruction not supported in Thumb16 mode --
`adds r3,#5'
| /tmp/ccQ4Z3ej.s:1201: Error: lo register required -- `ldr r10,[r1,#60]'
| /tmp/ccQ4Z3ej.s:1202: Error: lo register required -- `ldr r3,[r10,#0]'
| /tmp/ccQ4Z3ej.s:1216: Error: instruction not supported in Thumb16 mode --
`adds r3,#5'
| /tmp/ccQ4Z3ej.s:1234: Error: lo register required -- `ldr r10,[r1,#60]'
| /tmp/ccQ4Z3ej.s:1241: Error: dest must overlap one source register -- `mul
r2,r3,r0'
| /tmp/ccQ4Z3ej.s:1242: Error: instruction not supported in Thumb16 mode --
`lsls r0,r0,#3'
| /tmp/ccQ4Z3ej.s:1245: Error: unshifted register required -- `add
r3,r5,r0,lsl#0'
| /tmp/ccQ4Z3ej.s:1247: Error: instruction not supported in Thumb16 mode --
`subs r4,r4,#32'
| /tmp/ccQ4Z3ej.s:1249: Error: unshifted register required -- `add
r3,r5,r0,lsl#0'
| /tmp/ccQ4Z3ej.s:1252: Error: unshifted register required -- `mvn r3,#7'
| /tmp/ccQ4Z3ej.s:1253: Error: instruction not supported in Thumb16 mode --
`adds r0,r3'
| /tmp/ccQ4Z3ej.s:1261: Error: instruction not supported in Thumb16 mode --
`lsls r0,r0,#3'
| /tmp/ccQ4Z3ej.s:1262: Error: instruction not supported in Thumb16 mode --
`subs r0,r5,r0'

Removing LTO or -mthumb makes the problem go away.
$ ld --version
GNU ld (crosstool-NG 1.19.0 - 4.8-2014.10-x86_64) 2.24.0.20140311 Linaro
2014.03
Copyright 2013 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) a later version.
This program has absolutely no warranty.
$ gcc --version
gcc-original (crosstool-NG 1.19.0 - 4.8-2014.10-x86_64) 4.8.3 20140401
(prerelease)
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[Bug lto/45729] -flto conflicts with -mthumb

[chrbr at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45729

chrbr at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |chrbr at gcc dot gnu.org
         Depends on|                            |52144

--- Comment #4 from chrbr at gcc dot gnu.org ---
need to add __attribute__((noinline)) for f(void) to make sure it is compiled
in arm mode, otherwise it takes the mode of the caller


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52144
[Bug 52144] ARM should support arm/thumb function attribute to permit different
instruction sets in the same source

[Bug lto/45729] -flto conflicts with -mthumb

[chrbr at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45729
Bug 45729 depends on bug 52144, which changed state.

Bug 52144 Summary: ARM should support arm/thumb function attribute to permit different instruction sets in the same source
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52144

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

[Bug lto/45729] -flto conflicts with -mthumb

[ibolton at gcc dot gnu dot org]

------- Comment #1 from ibolton at gcc dot gnu dot org  2010-09-21 15:30 -------
Unfortunately, LTO does not officially work on ARM yet.  There are many LTO
failures in the gcc testsuite at the moment.

Can you retry without LTO so we can diagnose the interworking problems?


-- 

ibolton at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ibolton at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2010-09-21 15:30:17
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45729