Merge #18104: build: Skip i686 build by default in guix and gitian

fae9084 build: Skip i686 build by default in guix and gitian (MarcoFalke)
fa55a25 depends: Remove reference to win32 (MarcoFalke)

Pull request description:

  Closes #17504

  Now that we no longer provide downloads for i686 on our website (https://bitcoincore.org/en/download/), there is no need to build them by default.

  i686 can still be built in depends (tested by ci/travis) and in guix/gitian by setting the appropriate `HOSTS`.

ACKs for top commit:
  practicalswift:
    ACK fae9084 -- patch looks correct
  dongcarl:
    ACK fae9084 patch looks correct
  laanwj:
    Code review ACK fae9084
  hebasto:
    ACK fae9084, I have reviewed the code and it looks OK, I agree it can be merged.

Tree-SHA512: b000c19a2cd2a596a52028fa298c4022c24cfdfc1bdb3795a90916d0a00a32e4dd22278db93790b6a11724e08ea8451f4f05c77bc40d1664518e11a8c82d6e29

Author: fanquake

contrib/gitian-descriptors/gitian-linux.yml

@@ -40,7 +40,7 @@ script: |
   set -e -o pipefail
 
   WRAP_DIR=$HOME/wrapped
-  HOSTS="i686-pc-linux-gnu x86_64-linux-gnu arm-linux-gnueabihf aarch64-linux-gnu riscv64-linux-gnu"
+  HOSTS="x86_64-linux-gnu arm-linux-gnueabihf aarch64-linux-gnu riscv64-linux-gnu"
   CONFIGFLAGS="--enable-glibc-back-compat --enable-reduce-exports --disable-bench --disable-gui-tests"
   FAKETIME_HOST_PROGS="gcc g++"
   FAKETIME_PROGS="date ar ranlib nm"

contrib/guix/README.md

@@ -114,7 +114,7 @@ find output/ -type f -print0 | sort -z | xargs -r0 sha256sum
 * _**HOSTS**_
 
   Override the space-separated list of platform triples for which to perform a
-  bootstrappable build. _(defaults to "i686-linux-gnu x86\_64-linux-gnu
+  bootstrappable build. _(defaults to "x86\_64-linux-gnu
   arm-linux-gnueabihf aarch64-linux-gnu riscv64-linux-gnu")_
 
   > Windows and OS X platform triplet support are WIP.

contrib/guix/guix-build.sh

@@ -20,7 +20,7 @@ time-machine() {
 }
 
 # Deterministically build Bitcoin Core for HOSTs (overriable by environment)
-for host in ${HOSTS=i686-linux-gnu x86_64-linux-gnu arm-linux-gnueabihf aarch64-linux-gnu riscv64-linux-gnu}; do
+for host in ${HOSTS=x86_64-linux-gnu arm-linux-gnueabihf aarch64-linux-gnu riscv64-linux-gnu}; do
 
     # Display proper warning when the user interrupts the build
     trap 'echo "** INT received while building ${host}, you may want to clean up the relevant output and distsrc-* directories before rebuilding"' INT

depends/README.md

@@ -46,7 +46,7 @@ The paths are automatically configured and no other options are needed unless ta
 
     sudo apt-get install curl librsvg2-bin libtiff-tools bsdmainutils cmake imagemagick libcap-dev libz-dev libbz2-dev python3-setuptools
 
-#### For Win32/Win64 cross compilation
+#### For Win64 cross compilation
 
 - see [build-windows.md](../doc/build-windows.md#cross-compilation-for-ubuntu-and-windows-subsystem-for-linux)
 

doc/release-process.md

@@ -268,7 +268,6 @@ The list of files should be:
 ```
 bitcoin-${VERSION}-aarch64-linux-gnu.tar.gz
 bitcoin-${VERSION}-arm-linux-gnueabihf.tar.gz
-bitcoin-${VERSION}-i686-pc-linux-gnu.tar.gz
 bitcoin-${VERSION}-riscv64-linux-gnu.tar.gz
 bitcoin-${VERSION}-x86_64-linux-gnu.tar.gz
 bitcoin-${VERSION}-osx64.tar.gz