The 1.27 rust-stable bootstrap build step fails on mips64

[draganmladjenovic]

The error mesage is:

`error: linking with `cc` failed: exit code: 1
  |
  = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-L" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.138pesuvab4dy035.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.15kq92zzbmxot4k9.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.16u6js6g0l3k1ic6.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.1ckp3bwk0jmrbky4.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.1im38lueib99jsk0.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.1mvmz58owquyropc.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.1y16o1qfye96o7m0.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.1zeawhkbeobww1zn.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.1zwd8n7bcl3vhvvh.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.23tqyymcb18u96mb.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.2jqywn86b2gsqohu.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.2lyh15q6cjwzy18c.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.3171x0bwu82dptu7.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.35af7odfhiqsblci.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.3ayaeypdcro9d6yk.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.3cx7oljifvb206q7.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.3g94tobrpgum5dk6.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.3rngp6bm2u2q5z0y.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.43v6g0y2xsxoggnt.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.45nf4z58qqykpcpi.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.48721dc4k5qxei0u.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.49a7n47po4ttqjl7.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.4b8ptp1vn215jmoe.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.4dvpkvhelzqn37of.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.4xq48u46a1pwiqn7.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.4ybye971cqflgun6.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.4yh8x2b62dcih00t.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.4ypvbwho0bu5tnww.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.8xzrsc1ux72v29j.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.9elsx31vb4it187.rcgu.o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.e19kx9t7xhzajfl.rcgu.o" "-o" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50" "/home/draganm/work/rust/build/bootstrap/debug/deps/bootstrap-e1de2c0797369e50.crate.allocator.rcgu.o" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs" "-L" "/home/draganm/work/rust/build/bootstrap/debug/deps" "-L" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib" "-Wl,-Bstatic" "/home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libpetgraph-21e72575365cd228.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libordermap-5f1d6b4d32742667.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libfixedbitset-18048728a1801049.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libtime-736f43167516e58e.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libtoml-51916d91f90fa53e.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libnum_cpus-12ac34ed547f3180.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libgetopts-2a463d2722dba7b8.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libfiletime-c8a8e6c0f3aa27b0.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/liblibc-2d42ca337778fc07.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libcfg_if-cf754c2e7fcf3720.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libcmake-72d576f6c4aa644f.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libcc-6cc2976f70db579f.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libserde_json-9db09363bcefa01f.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libitoa-9993a924e130a429.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libdtoa-ca37bbda1bb7c5a0.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libserde-9d7a61a020c48540.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libnum_traits-77a6d928f7bf0203.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/liblazy_static-83ca103b78acf207.rlib" "/home/draganm/work/rust/build/bootstrap/debug/deps/libbuild_helper-807bedf9f7568fde.rlib" "-Wl,--start-group" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/libstd-8d847bbe97fc9dc5.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/libpanic_unwind-008c42aad548e7dd.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/libunwind-0fe53371ec419e32.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/liballoc_system-9dec1cbd51097ce1.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/liblibc-6a4fb915dd86d140.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/liballoc-7ebba6af2d3cc324.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/libstd_unicode-7a26f8b3cf380464.rlib" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/libcore-b0c2d164a9741309.rlib" "-Wl,--end-group" "/home/draganm/work/rust/build/mips64el-unknown-linux-gnuabi64/stage0/lib/rustlib/mips64el-unknown-linux-gnuabi64/lib/libcompiler_builtins-66d072e25a9acee3.rlib" "-Wl,-Bdynamic" "-l" "util" "-l" "dl" "-l" "rt" "-l" "pthread" "-l" "gcc_s" "-l" "c" "-l" "m" "-l" "rt" "-l" "pthread" "-l" "util"
  = note: /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `<std::collections::hash::map::HashMap<K, V, S> as core::clone::Clone>::clone':
          /checkout/src/libstd/collections/hash/map.rs:399:(.text._ZN102_$LT$std..collections..hash..map..HashMap$LT$K$C$$u20$V$C$$u20$S$GT$$u20$as$u20$core..clone..Clone$GT$5clone17hde56aa8496891c67E+0x8c): relocation truncated to fit: R_MIPS_CALL16 against `_Unwind_Resume@@GCC_3.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `<std::collections::hash::map::HashMap<K, V, S> as core::iter::traits::IntoIterator>::into_iter':
          /checkout/src/libstd/collections/hash/map.rs:1834:(.text._ZN116_$LT$std..collections..hash..map..HashMap$LT$K$C$$u20$V$C$$u20$S$GT$$u20$as$u20$core..iter..traits..IntoIterator$GT$9into_iter17h3971322724732454E+0x84): relocation truncated to fit: R_MIPS_CALL16 against `_Unwind_Resume@@GCC_3.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `<std::collections::hash::map::HashMap<K, V, S> as core::iter::traits::Extend<(K, V)>>::extend':
          /checkout/src/libstd/collections/hash/map.rs:2581:(.text._ZN136_$LT$std..collections..hash..map..HashMap$LT$K$C$$u20$V$C$$u20$S$GT$$u20$as$u20$core..iter..traits..Extend$LT$$LP$K$C$$u20$V$RP$$GT$$GT$6extend17h8b839c2a084c624aE+0xcc): relocation truncated to fit: R_MIPS_CALL16 against `_Unwind_Resume@@GCC_3.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `<std::collections::hash::map::HashMap<K, V, S> as core::iter::traits::Extend<(K, V)>>::extend':
          /checkout/src/libstd/collections/hash/map.rs:2581:(.text._ZN136_$LT$std..collections..hash..map..HashMap$LT$K$C$$u20$V$C$$u20$S$GT$$u20$as$u20$core..iter..traits..Extend$LT$$LP$K$C$$u20$V$RP$$GT$$GT$6extend17hb662b5607a17e017E+0xb4): relocation truncated to fit: R_MIPS_CALL16 against `_Unwind_Resume@@GCC_3.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `<std::collections::hash::map::InternalEntry<K, V, &'a mut std::collections::hash::table::RawTable<K, V>>>::into_entry':
          /checkout/src/libstd/collections/hash/map.rs:1680:(.text._ZN157_$LT$std..collections..hash..map..InternalEntry$LT$K$C$$u20$V$C$$u20$$RF$$u27$a$u20$mut$u20$std..collections..hash..table..RawTable$LT$K$C$$u20$V$GT$$GT$$GT$10into_entry17h96e9d8440f6f2c01E+0x2ac): relocation truncated to fit: R_MIPS_CALL16 against `memcpy@@GLIBC_2.0'
          /checkout/src/libstd/collections/hash/map.rs:1686:(.text._ZN157_$LT$std..collections..hash..map..InternalEntry$LT$K$C$$u20$V$C$$u20$$RF$$u27$a$u20$mut$u20$std..collections..hash..table..RawTable$LT$K$C$$u20$V$GT$$GT$$GT$10into_entry17h96e9d8440f6f2c01E+0x44c): relocation truncated to fit: R_MIPS_CALL16 against `memcpy@@GLIBC_2.0'
          /checkout/src/libstd/collections/hash/map.rs:1686:(.text._ZN157_$LT$std..collections..hash..map..InternalEntry$LT$K$C$$u20$V$C$$u20$$RF$$u27$a$u20$mut$u20$std..collections..hash..table..RawTable$LT$K$C$$u20$V$GT$$GT$$GT$10into_entry17h96e9d8440f6f2c01E+0x478): relocation truncated to fit: R_MIPS_CALL16 against `memcpy@@GLIBC_2.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `<std::collections::hash::map::InternalEntry<K, V, &'a mut std::collections::hash::table::RawTable<K, V>>>::into_entry':
          /checkout/src/libstd/collections/hash/map.rs:1680:(.text._ZN157_$LT$std..collections..hash..map..InternalEntry$LT$K$C$$u20$V$C$$u20$$RF$$u27$a$u20$mut$u20$std..collections..hash..table..RawTable$LT$K$C$$u20$V$GT$$GT$$GT$10into_entry17he24a1b5fedc0b2f6E+0x26c): relocation truncated to fit: R_MIPS_CALL16 against `memcpy@@GLIBC_2.0'
          /checkout/src/libstd/collections/hash/map.rs:1686:(.text._ZN157_$LT$std..collections..hash..map..InternalEntry$LT$K$C$$u20$V$C$$u20$$RF$$u27$a$u20$mut$u20$std..collections..hash..table..RawTable$LT$K$C$$u20$V$GT$$GT$$GT$10into_entry17he24a1b5fedc0b2f6E+0x46c): relocation truncated to fit: R_MIPS_CALL16 against `memcpy@@GLIBC_2.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `std::collections::hash::map::robin_hood':
          /checkout/src/libstd/collections/hash/map.rs:503:(.text._ZN3std11collections4hash3map10robin_hood17h012217733b3b4b5aE+0xa4): relocation truncated to fit: R_MIPS_CALL16 against `_Unwind_Resume@@GCC_3.0'
          /home/draganm/work/rust/build/bootstrap/debug/deps/libbootstrap-ae75a7d683cd3583.rlib(bootstrap-ae75a7d683cd3583.2w6xsa2hbi53xhak.rcgu.o): In function `std::collections::hash::map::robin_hood':
          /checkout/src/libstd/collections/hash/map.rs:503:(.text._ZN3std11collections4hash3map10robin_hood17h03200646b79056ceE+0xa4): additional relocation overflows omitted from the output`

Not sure yet if there is a bug behind this. Posting this here just in case.

What happens is that we hit the limit of 8K GOT entries per single object file. I've tried using 1.25 instead of 1.26 as bootstrap compiler and the bootstrap build passes with offending object file having ~7K symbols needing GOT entry. I haven't been able to find exact reason for this. At first glance, while it sound counterintuitive, it seems that we have more inlining on 1.26 which pulls in more symbol references.

I was able to sidestep this by increasing opt-level for bootstrap build to 3. As a stopgap, is it ok to provide and option to bootstrap.py to build bootstrap tool in release mode ? I can send the PR.

[Mark-Simulacrum]

cc @michaelwoerister @rust-lang/compiler -- marking a stable/stable regression. I'm not sure what could cause this (bootstrap is fairly small).

[pnkfelix]

visiting for triage.

Some notes, in part to self: mips64 is a tier 2 platform. We support building the tools (but not testing them) for such platforms ... and unfortunately we are doing such building via cross-compiles, so our continuous-integration system didn't catch whatever caused the build of bootstrap to start failing.

Marking at P-medium for now.

@draganmladjenovic I think we would be happy to look at any PR you provide that gives a way to sidestep the issue you are facing as long as it does not change the default behavior....

[sanxiyn]

GCC MIPS documentation suggests that you should use -mxgot if you see "relocation truncated to fit" errors.

[jiangtao9999]

@sanxiyn
Add -mxgot with cc command ?It seems not usefull ...
export RUSTFLAGS=-Clink-arg=-mxgot ? It seems not pass to linker ....

sh-4.4# ls which cc -l
lrwxrwxrwx 1 root root 3 Jul 20 00:44 /usr/bin/cc -> gcc
sh-4.4# cat /usr/bin/cc
#!/bin/bash
exec /usr/bin/gcc.aaa -mxgot -Wa,-xgot $@
sh-4.4#

Output
mock's build.log
build.log

[draganmladjenovic]

@jiangtao9999 I haven't tested it but I think you should use RUSTFLAGS="-C llvm-args=-mxgot".
Edit: Also note that bootstrap tool build sets its own RUSTFLAGS https://github.com/rust-lang/rust/blob/master/src/bootstrap/bootstrap.py#L622 .

[jiangtao9999]

@draganmladjenovic
Add this line in the .spec file:
sed -i 's/-Cdebuginfo=2/-Cdebuginfo=2 -C llvm-args=-mxgot/' src/bootstrap/bootstrap.py
And RPMs were built successful .
🤗🤗

[wzssyqa]

With this patch, rustc can build on mips64el.

Index: rustc-1.27.1+dfsg1/src/bootstrap/bootstrap.py
===================================================================
--- rustc-1.27.1+dfsg1.orig/src/bootstrap/bootstrap.py
+++ rustc-1.27.1+dfsg1/src/bootstrap/bootstrap.py
@@ -591,6 +591,8 @@ class RustBuild(object):
             (os.pathsep + env["LIBRARY_PATH"]) \
             if "LIBRARY_PATH" in env else ""
         env["RUSTFLAGS"] = "-Cdebuginfo=2"
+        if self.build_triple().startswith('mips'):
+            env["RUSTFLAGS"] += " -Cllvm-args=-mxgot"
         env["PATH"] = os.path.join(self.bin_root(), "bin") + \
             os.pathsep + env["PATH"]
         if not os.path.isfile(self.cargo()):

[infinity0]

Is this needed all the time? (What's special about the bootstrap process?) If it's needed all the time, perhaps rustc should always be passing that flag to LLVM? In which case the change should be made to a more internal file, bootstrap.py only applies when compiling rustc itself.