Rollup merge of #39068 - alexcrichton:more-small-tests, r=brson

travis: Add i586 linux and i686 musl

This commit expands the existing x86_64-musl entry in the Travis matrix to also
build/test i586-unknown-linux-gnu and i686-unknown-linux-musl.

cc #38531
Closes #35599
Closes #39053

4 files changed, 96 insertions, 41 deletions

diff --git a/src/ci/docker/x86_64-musl/Dockerfile b/src/ci/docker/linux-tested-targets/Dockerfile
index 11b85a6c8fd..2a43201ed0a 100644
--- a/src/ci/docker/x86_64-musl/Dockerfile
+++ b/src/ci/docker/linux-tested-targets/Dockerfile
@@ -1,7 +1,7 @@
 FROM ubuntu:16.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-  g++ \
+  g++-multilib \
   make \
   file \
   curl \
@@ -11,10 +11,11 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   xz-utils \
   sudo \
-  gdb
+  gdb \
+  patch
 
 WORKDIR /build/
-COPY build-musl.sh /build/
+COPY musl-libunwind-patch.patch build-musl.sh /build/
 RUN sh /build/build-musl.sh && rm -rf /build
 
 RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-init_1.2.0_amd64.deb && \
@@ -27,9 +28,17 @@ RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST |
       tar xJf - -C /usr/local/bin --strip-components=1
 
 ENV RUST_CONFIGURE_ARGS \
-      --target=x86_64-unknown-linux-musl \
-      --musl-root-x86_64=/musl-x86_64
-ENV PATH=$PATH:/musl-x86_64/bin
+      --target=x86_64-unknown-linux-musl,i686-unknown-linux-musl,i586-unknown-linux-gnu \
+      --musl-root-x86_64=/musl-x86_64 \
+      --musl-root-i686=/musl-i686
+
 ENV SCRIPT \
-      python2.7 ../x.py test --target x86_64-unknown-linux-musl && \
-      python2.7 ../x.py dist --target x86_64-unknown-linux-musl
+      python2.7 ../x.py test \
+          --target x86_64-unknown-linux-musl \
+          --target i686-unknown-linux-musl \
+          --target i586-unknown-linux-gnu \
+          && \
+      python2.7 ../x.py dist \
+          --target x86_64-unknown-linux-musl \
+          --target i686-unknown-linux-musl \
+          --target i586-unknown-linux-gnu
diff --git a/src/ci/docker/linux-tested-targets/build-musl.sh b/src/ci/docker/linux-tested-targets/build-musl.sh
new file mode 100644
index 00000000000..2382605f9bd
--- /dev/null
+++ b/src/ci/docker/linux-tested-targets/build-musl.sh
@@ -0,0 +1,64 @@
+#!/bin/sh
+# Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+export CFLAGS="-fPIC"
+MUSL=musl-1.1.14
+curl https://www.musl-libc.org/releases/$MUSL.tar.gz | tar xzf -
+cd $MUSL
+./configure --prefix=/musl-x86_64 --disable-shared
+make -j10
+make install
+make clean
+# for i686
+CFLAGS="$CFLAGS -m32" ./configure --prefix=/musl-i686 --disable-shared --target=i686
+make -j10
+make install
+cd ..
+
+# To build MUSL we're going to need a libunwind lying around, so acquire that
+# here and build it.
+curl -L https://github.com/llvm-mirror/llvm/archive/release_37.tar.gz | tar xzf -
+curl -L https://github.com/llvm-mirror/libunwind/archive/release_37.tar.gz | tar xzf -
+
+# Whoa what's this mysterious patch we're applying to libunwind! Why are we
+# swapping the values of ESP/EBP in libunwind?!
+#
+# Discovered in #35599 it turns out that the vanilla build of libunwind is not
+# suitable for unwinding 32-bit musl. After some investigation it ended up
+# looking like the register values for ESP/EBP were indeed incorrect (swapped)
+# in the source. Similar commits in libunwind (r280099 and r282589) have noticed
+# this for other platforms, and we just need to realize it for musl linux as
+# well.
+#
+# More technical info can be found at #35599
+cd libunwind-release_37
+patch -Np1 < /build/musl-libunwind-patch.patch
+cd ..
+
+mkdir libunwind-build
+cd libunwind-build
+cmake ../libunwind-release_37 -DLLVM_PATH=/build/llvm-release_37 \
+          -DLIBUNWIND_ENABLE_SHARED=0
+make -j10
+cp lib/libunwind.a /musl-x86_64/lib
+
+# (Note: the next cmake call doesn't fully override the previous cached one, so remove the cached
+# configuration manually. IOW, if don't do this or call make clean we'll end up building libunwind
+# for x86_64 again)
+rm -rf *
+# for i686
+CFLAGS="$CFLAGS -m32 -g" CXXFLAGS="$CXXFLAGS -m32 -g" cmake ../libunwind-release_37 \
+          -DLLVM_PATH=/build/llvm-release_37 \
+          -DLIBUNWIND_ENABLE_SHARED=0
+make -j10
+cp lib/libunwind.a /musl-i686/lib
diff --git a/src/ci/docker/linux-tested-targets/musl-libunwind-patch.patch b/src/ci/docker/linux-tested-targets/musl-libunwind-patch.patch
new file mode 100644
index 00000000000..99cd685b72d
--- /dev/null
+++ b/src/ci/docker/linux-tested-targets/musl-libunwind-patch.patch
@@ -0,0 +1,15 @@
+diff --git a/include/libunwind.h b/include/libunwind.h
+index c5b9633..1360eb2 100644
+--- a/include/libunwind.h
++++ b/include/libunwind.h
+@@ -151,8 +151,8 @@ enum {
+   UNW_X86_ECX = 1,
+   UNW_X86_EDX = 2,
+   UNW_X86_EBX = 3,
+-  UNW_X86_EBP = 4,
+-  UNW_X86_ESP = 5,
++  UNW_X86_ESP = 4,
++  UNW_X86_EBP = 5,
+   UNW_X86_ESI = 6,
+   UNW_X86_EDI = 7
+ };
diff --git a/src/ci/docker/x86_64-musl/build-musl.sh b/src/ci/docker/x86_64-musl/build-musl.sh
deleted file mode 100644
index 2bfbd646b75..00000000000
--- a/src/ci/docker/x86_64-musl/build-musl.sh
+++ /dev/null
@@ -1,33 +0,0 @@
-#!/bin/sh
-# Copyright 2016 The Rust Project Developers. See the COPYRIGHT
-# file at the top-level directory of this distribution and at
-# http://rust-lang.org/COPYRIGHT.
-#
-# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-# option. This file may not be copied, modified, or distributed
-# except according to those terms.
-
-set -ex
-
-export CFLAGS="-fPIC"
-MUSL=musl-1.1.14
-curl https://www.musl-libc.org/releases/$MUSL.tar.gz | tar xzf -
-cd $MUSL
-./configure --prefix=/musl-x86_64 --disable-shared
-make -j10
-make install
-make clean
-cd ..
-
-# To build MUSL we're going to need a libunwind lying around, so acquire that
-# here and build it.
-curl -L https://github.com/llvm-mirror/llvm/archive/release_37.tar.gz | tar xzf -
-curl -L https://github.com/llvm-mirror/libunwind/archive/release_37.tar.gz | tar xzf -
-mkdir libunwind-build
-cd libunwind-build
-cmake ../libunwind-release_37 -DLLVM_PATH=/build/llvm-release_37 \
-          -DLIBUNWIND_ENABLE_SHARED=0
-make -j10
-cp lib/libunwind.a /musl-x86_64/lib