Re: [scarthgap] recipe's sysroot misconfiguration in multilib

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Wed, 2025-03-26 at 19:47 +0100, Joao Marcos Costa wrote:
> I have been trying to set up a multilib environment to generate 
> libraries built with Control Flow Integrity support. The gcc toolchain 
> is already patched to support this custom multilib ABI, and it is indeed 
> capable of generating binaries with the CFI flags.
> 
> I am, however, facing this strange issue where a header is not found in 
> the multilib recipe-sysroot (i.e., libcfi-recipe-sysroot) of a given 
> package (e.g., zstd), and do_compile task fails:
> 
> libcfi-zstd/1.5.5/libcfi-recipe-sysroot/usr/include/c++/13.2.0/cstdint:38:10: 
> fatal error: bits/c++config.h: No such file or directory
> >    38 | #include <bits/c++config.h>
> >       |          ^~~~~~~~~~~~~~~~~~
> > compilation terminated.
> > make: *** [Makefile:248: Options.o] Error 1
> 
> The strange part is the header is there:
> libcfi-recipe-sysroot/usr/include/c++/13.2.0/riscv64-freedomusdkmllibcfi-linux/bits/c++config.h
> 
> Another strange aspect in this very same context is: the 
> recipe-sysroot-native seems misconfigured and incomplete. For reference, 
> let me use libcfi-zstd/zstd again:
> 
> zstd/1.5.5$ ls recipe-sysroot-native/sysroot-providers/ -l | wc -l
> 66
> zstd/1.5.5$ du -sh recipe-sysroot-native/
> 457M	recipe-sysroot-native/
> 
> libcfi-zstd/1.5.5$ ls recipe-sysroot-native/sysroot-providers/ -l | wc -l
> 27
> libcfi-zstd/1.5.5$ du -sh recipe-sysroot-native/
> 194M	recipe-sysroot-native/
> 
> Unless I'm missing something, shouldn't I have roughly the same values here?
> 
> Besides my TUNE_*, DEFAULTTUNE, BASE_LIB values set up, I also added
> 'GCCMULTILIB = "--enable-multilib"' to gcc-cross.inc, to enable multilib 
> for the cross toolchain. Could I be missing something, maybe with
> recipes-devtools/gcc/gcc-multilib-config.inc?

I'm finding it odd that you have to add --enable-multilib since in
general with gcc-cross, we use separate cross toolchains for each
multilib. This kind of implies you're configuring the setup differently
to how the system would expect.

The recipe-sysroot-native/installeddeps/ directory will show you what
is installed in each and might help narrow down the size difference.

Cheers,

Richard