https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60160
R. Diez <rdiezmail-gcc at yahoo dot de> changed:
What |Removed |Added
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CC| |rdiezmail-gcc at yahoo dot de
--- Comment #6 from R. Diez <rdiezmail-gcc at yahoo dot de> ---
I am experimenting with a GCC 11.2 cross-compiler for bare-metal embedded
software.
There is no operating system, so no shared libraries or anything fancy. But
there is a static libc (Newlib or Picolibc).
I wanted to build everything with LTO, including libc, libstdc++ and libgcc.
This is the makefile I am using:
https://github.com/rdiez/JtagDue/blob/master/Toolchain/Makefile
Search for "-ffat-lto-objects" in that makefile.
As soon as I enable the LTO flags, I get linker errors. They are documented in
the makefile next to the LTO options, and look similar to those reported in
this bug.
I tried -fno-builtin with varying degrees of success. I also tried building
only the application and libc with LTO, but not libstdc++ etc., to no avail.
LTO only works for the user application. As soon as libc or the other GCC
libraries are compiled with LTO, it fails.
Is it unfortunate, because I believe that a full LTO build for a bare-metal
environment would be rather beneficial.
The patch and information referenced in this bug report look dated. Is there a
way to make LTO work now, at least for my configuration?
