[PATCH 2/2] ci: add mingw cross compilation in GHA

[David Marchand <david.marchand@redhat.com>]

Add mingw cross compilation in our public CI so that users with their
own github repository have a first level of checks for Windows compilation
before submitting to the mailing list.
This does not replace our better checks in other entities of the CI.

Only the helloworld example is compiled (same as what is tested in
test-meson-builds.sh).

Note: the mingw cross compilation toolchain (version 5.0) in Ubuntu
18.04 was broken (missing a ENOMSG definition).

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 .ci/linux-build.sh          | 22 +++++++++++++++++-----
 .github/workflows/build.yml |  8 ++++++++
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/.ci/linux-build.sh b/.ci/linux-build.sh
index 30119b61ba..06dd20772d 100755
--- a/.ci/linux-build.sh
+++ b/.ci/linux-build.sh
@@ -37,16 +37,26 @@ catch_coredump() {
     return 1
 }
 
+cross_file=
+
 if [ "$AARCH64" = "true" ]; then
     if [ "${CC%%clang}" != "$CC" ]; then
-        OPTS="$OPTS --cross-file config/arm/arm64_armv8_linux_clang_ubuntu2004"
+        cross_file=config/arm/arm64_armv8_linux_clang_ubuntu2004
     else
-        OPTS="$OPTS --cross-file config/arm/arm64_armv8_linux_gcc"
+        cross_file=config/arm/arm64_armv8_linux_gcc
     fi
 fi
 
+if [ "$MINGW" = "true" ]; then
+    cross_file=config/x86/cross-mingw
+fi
+
 if [ "$PPC64LE" = "true" ]; then
-    OPTS="$OPTS --cross-file config/ppc/ppc64le-power8-linux-gcc-ubuntu2004"
+    cross_file=config/ppc/ppc64le-power8-linux-gcc-ubuntu2004
+fi
+
+if [ -n "$cross_file" ]; then
+    OPTS="$OPTS --cross-file $cross_file"
 fi
 
 if [ "$BUILD_DOCS" = "true" ]; then
@@ -59,7 +69,9 @@ if [ "$BUILD_32BIT" = "true" ]; then
     export PKG_CONFIG_LIBDIR="/usr/lib32/pkgconfig"
 fi
 
-if [ "$DEF_LIB" = "static" ]; then
+if [ "$MINGW" = "true" ]; then
+    OPTS="$OPTS -Dexamples=helloworld"
+elif [ "$DEF_LIB" = "static" ]; then
     OPTS="$OPTS -Dexamples=l2fwd,l3fwd"
 else
     OPTS="$OPTS -Dexamples=all"
@@ -76,7 +88,7 @@ fi
 meson build --werror $OPTS
 ninja -C build
 
-if [ "$AARCH64" != "true" ] && [ "$PPC64LE" != "true" ]; then
+if [ -z "$cross_file" ]; then
     failed=
     configure_coredump
     devtools/test-null.sh || failed="true"
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 812aa7055d..e2f94d786b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -21,6 +21,7 @@ jobs:
       CC: ccache ${{ matrix.config.compiler }}
       DEF_LIB: ${{ matrix.config.library }}
       LIBABIGAIL_VERSION: libabigail-1.8
+      MINGW: ${{ matrix.config.cross == 'mingw' }}
       MINI: ${{ matrix.config.mini != '' }}
       PPC64LE: ${{ matrix.config.cross == 'ppc64le' }}
       REF_GIT_TAG: v22.03
@@ -52,6 +53,10 @@ jobs:
             compiler: gcc
             library: static
             cross: i386
+          - os: ubuntu-20.04
+            compiler: gcc
+            library: static
+            cross: mingw
           - os: ubuntu-20.04
             compiler: gcc
             library: static
@@ -119,6 +124,9 @@ jobs:
       if: env.AARCH64 == 'true'
       run: sudo apt install -y gcc-aarch64-linux-gnu libc6-dev-arm64-cross
         pkg-config-aarch64-linux-gnu
+    - name: Install mingw cross compiling packages
+      if: env.MINGW == 'true'
+      run: sudo apt install -y mingw-w64 mingw-w64-tools
     - name: Install ppc64le cross compiling packages
       if: env.PPC64LE == 'true'
       run: sudo apt install -y gcc-powerpc64le-linux-gnu libc6-dev-ppc64el-cross
-- 
2.23.0