Auto merge of rust-lang#70414 - lopsided98:armv6-gcc-8, r=pietroalbini

Upgrade GCC to 8.3.0, glibc to 2.17.0 and crosstool-ng to 1.24.0 for dist-arm-linux and dist-armhf-linux

Attempt to fix rust-lang#69420 in the same manner as rust-lang#65302 did for armv7l. I have tested that this eliminates the segfault while building a `hello_world` package on `arm-unknown-linux-gnueabihf`.

I have not been able to test whether the bug exists for `arm-unknown-linux-gnueabi` as well, but I suspect it does, so I upgraded the toolchain for that platform as well.

src/ci/docker/README.md

@@ -138,33 +138,31 @@ $category > $option = $value -- $comment
 For targets: `arm-unknown-linux-gnueabi`
 
 - Path and misc options > Prefix directory = /x-tools/${CT\_TARGET}
-- Path and misc options > Patches origin = Bundled, then local
-- Path and misc options > Local patch directory = /tmp/patches
+- Path and misc options > Patches origin = Bundled only
 - Target options > Target Architecture = arm
 - Target options > Architecture level = armv6 -- (+)
 - Target options > Floating point = software (no FPU) -- (\*)
 - Operating System > Target OS = linux
-- Operating System > Linux kernel version = 3.2.72 -- Precise kernel
-- C-library > glibc version = 2.16.0
-- C compiler > gcc version = 5.2.0
+- Operating System > Linux kernel version = 3.2.101
+- C-library > glibc version = 2.17.0
+- C compiler > gcc version = 8.3.0
 - C compiler > C++ = ENABLE -- to cross compile LLVM
 
 ### `arm-linux-gnueabihf.config`
 
 For targets: `arm-unknown-linux-gnueabihf`
 
 - Path and misc options > Prefix directory = /x-tools/${CT\_TARGET}
-- Path and misc options > Patches origin = Bundled, then local
-- Path and misc options > Local patch directory = /tmp/patches
+- Path and misc options > Patches origin = Bundled only
 - Target options > Target Architecture = arm
 - Target options > Architecture level = armv6 -- (+)
 - Target options > Use specific FPU = vfp -- (+)
 - Target options > Floating point = hardware (FPU) -- (\*)
 - Target options > Default instruction set mode = arm -- (+)
 - Operating System > Target OS = linux
-- Operating System > Linux kernel version = 3.2.72 -- Precise kernel
-- C-library > glibc version = 2.16.0
-- C compiler > gcc version = 5.2.0
+- Operating System > Linux kernel version = 3.2.101
+- C-library > glibc version = 2.17.0
+- C compiler > gcc version = 8.3.0
 - C compiler > C++ = ENABLE -- to cross compile LLVM
 
 ### `armv7-linux-gnueabihf.config`

src/ci/docker/dist-arm-linux/Dockerfile

@@ -3,20 +3,14 @@ FROM ubuntu:16.04
 COPY scripts/cross-apt-packages.sh /scripts/
 RUN sh /scripts/cross-apt-packages.sh
 
-# Ubuntu 16.04 (this container) ships with make 4, but something in the
-# toolchains we build below chokes on that, so go back to make 3
-COPY scripts/make3.sh /scripts/
-RUN sh /scripts/make3.sh
-
-COPY scripts/crosstool-ng.sh /scripts/
-RUN sh /scripts/crosstool-ng.sh
+COPY scripts/crosstool-ng-1.24.sh /scripts/
+RUN sh /scripts/crosstool-ng-1.24.sh
 
 COPY scripts/rustbuild-setup.sh /scripts/
 RUN sh /scripts/rustbuild-setup.sh
 USER rustbuild
 WORKDIR /tmp
 
-COPY dist-arm-linux/patches/ /tmp/patches/
 COPY dist-arm-linux/arm-linux-gnueabi.config dist-arm-linux/build-toolchains.sh /tmp/
 RUN ./build-toolchains.sh