bug#35519: librsvg broken on i686-linux

["Ludovic Courtès" <ludo@gnu.org>]

Hello Danny and all,

Ricardo Wurmus <rekado@elephly.net> skribis:

>> Hydra failed to build librsvg on i686-linux, because it depends on Rust
>> which is still broken on i686-linux in Guix.
>
> Danny opened a bug report with the mrustc upstream:
>
>     https://github.com/thepowersgang/mrustc/issues/108
>
> The last message there tells us to try again with current HEAD on
> master.  If this fails I think it’s acceptable to use a binary for the
> very first Rust on i686; we would skip the use of mrustc on i686 then.
> Not great.

I don’t know if it relates but on current ‘core-updates’ Rust 1.19 fails
to build on i686:

--8<---------------cut here---------------start------------->8---
BUILDING curl_sys from curl-sys v0.3.11 with features []
> /gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/bin/mrustc src/vendor/curl-sys/lib.rs --crate-name curl_sys --crate-type rlib --crate-tag 0_3_11 -g --cfg debug_assertions -O -o output/cargo-build/libcurl_sys-0_3_11.hir -L output/cargo-build -L /gnu/store/44sdci2mizpvd70zyvbfs9ai0maw255z-curl-7.65.3/lib -l curl --extern libz_sys=output/cargo-build/liblibz_sys-1_0_13.hir --extern libc=output/cargo-build/liblibc-0_2_22.hir --extern openssl_sys=output/cargo-build/libopenssl_sys-0_9_12.hir -L output -L /gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/lib/mrust
BUILDING curl from curl v0.4.6 with features []
> /gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/bin/mrustc src/vendor/curl/src/lib.rs --crate-name curl --crate-type rlib --crate-tag 0_4_6 -g --cfg debug_assertions -O -o output/cargo-build/libcurl-0_4_6.hir -L output/cargo-build --extern libc=output/cargo-build/liblibc-0_2_22.hir --extern curl_sys=output/cargo-build/libcurl_sys-0_3_11.hir --extern openssl_sys=output/cargo-build/libopenssl_sys-0_9_12.hir --extern openssl_probe=output/cargo-build/libopenssl_probe-0_1_1.hir -L output -L /gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/lib/mrust
BUILDING crates_io from crates-io v0.9.0 with features []
> /gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/bin/mrustc src/tools/cargo/src/crates-io/lib.rs --crate-name crates_io --crate-type rlib --crate-tag 0_9_0 -g --cfg debug_assertions -O -o output/cargo-build/libcrates_io-0_9_0.hir -L output/cargo-build --extern curl=output/cargo-build/libcurl-0_4_6.hir --extern error_chain=output/cargo-build/liberror_chain-0_10_0.hir --extern serde=output/cargo-build/libserde-1_0_6.hir --extern serde_derive=output/cargo-build/libserde_derive-1_0_6.hir --extern serde_json=output/cargo-build/libserde_json-1_0_2.hir --extern url=output/cargo-build/liburl-1_4_0.hir -L output -L /gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/lib/mrust
munmap_chunk(): invalid pointer
src/tools/cargo/src/crates-io/lib.rs:65: BUG:src/expand/proc_macro.cpp:941: Unexpected EOF while reading from child process
BUILD FAILED
command "/gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/tools/bin/minicargo" "src/tools/cargo" "--vendor-dir" "src/vendor" "--output-dir" "output/cargo-build" "-L" "output/" "-L" "/gnu/store/2fh0bz69j6gxpgj5nqiqplwmck1dvi47-mrustc-0.8.0/lib/mrust" "-j" "1" failed with status 1
builder for `/gnu/store/01mh2n7mif0k49ivj6y3fdq1ssj3d2lq-rust-1.19.0.drv' failed with exit code 1
--8<---------------cut here---------------end--------------->8---

(From
<https://ci.guix.gnu.org/log/cnxzabs1mi42rfvz8gp34lqap0dwi9l6-rust-1.19.0-cargo>.)

Does that ring a bell?  Any ideas of a fix or workaround we could apply?

It’d be great if we could merge ‘core-updates’ soon.  This is
unfortunately not a regression compared to ‘master’, so I don’t think
this is a blocker.

Thoughts?

Ludo’.