Error when compiling screen, target arm-none-eabi

[knc1]

Originally Posted by ppoo

How to disable LTO ?

LTO is implemented as a (the only at the moment) "Plug-in"
So: -f <whatever gcc help tells you is disable-plug-ins is>
OR,
The links to the gcc on-line manual set is indexed in the "Tools" prefix index if your 'gcc help' isn't helpful enough.

[ppoo]

@knc1: I still gets gcc: fatal error: -fuse-linker-plugin, but liblto_plugin.so not found
and don't know how to fix it. Is there any arguments to disable it when compiling toolchain?

[knc1]

Originally Posted by ppoo

@knc1: I still gets gcc: fatal error: -fuse-linker-plugin, but liblto_plugin.so not found
and don't know how to fix it. Is there any arguments to disable it when compiling toolchain?

There probably is, but why not: -fno-use-linker-plugin when you don't want it?

Or, maybe just stop telling it to use the linker plug-in if you don't want it?
I.E: remove: -fuse-linker-plugin

I am probably not your best source of information on this subject.
Others here are much more experienced with these "new" tool-chain features than I.

[NiLuJe]

@ppoo: I'm not familiar with sb, but there should be an option somewhere to:

* Enable/Disable LTO support for GCC
* Enable/Disable plugins support for binutils

Barring that, -fno-lto -fno-use-linker-plugin in the CFLAGS

[knc1]

Originally Posted by NiLuJe

@ppoo: I'm not familiar with sb, but there should be an option somewhere to:

* Enable/Disable LTO support for GCC
* Enable/Disable plugins support for binutils

Barring that, -fno-lto -fno-use-linker-plugin in the CFLAGS

I am pretty sure that you can define in the sb2 instance things like "instance flags" for those options that will always be part of each use.

Little actual experience, but I seem to recall that in the docs.

An since that is a linker option (Link Time Optimization) it may have to go into LDFLAGS (maybe "also" into LDFLAGS).

[NiLuJe]

@knc1: A lot of broken buildsystems actually can't make use of LTO, because, yes, it has to be passed both at compile time & link time. If the buildsystem link through GCC, and passes the CFLAGS along with LDFLAGS, all is good, if not, GCC just spent its time churning out data that'll just end up being discarded . But it's still a GCC option, not a binutils one, so it's rightful place is still in CFLAGS, not LDFLAGS .

[knc1]

Ah, so -
So "both" would be the safest course in actual practice, at least until GCC starts throwing "unrecognized option for ..." errors.

(OR maybe the message(s) are: "xxx option used but yyy step not being preformed" - one of those "improvements" to GCC option handling recently introduced to drive Makefile authors crazy.)

[NiLuJe]

@knc1: The issue with putting it in LDFLAGS is that if one were to pass those to ld directly, not through a compiler driver like gcc, ld/gold would (probably, haven't checked) choke on -flto. And even through a driver, since it's not 'escaped' by -Wl, ld would probably not be a happy camper. And if you put it escaped in LDFLAGS, go back to square 1: ld chokes on it ^^.

Long story short: It's a GCC flag/feature, it goes in CFLAGS. Don't try to use it though any other means . The buildsystem just has to be 'smart' enough to link through the gcc linker driver, and to honor the *FLAGS properly.

[ppoo]

I put -fno-lto -fno-use-linker-plugin to host compiler flag and don't choose Enable LTO when compiling TC, and it run well.