ci: Add support for LLVM for Windows targets

It uses LLVM MinGW project to get the precompiled LLVM toolchain for
cross-compilation.

Signed-off-by: Marek Pikuła <m.pikula@partner.samsung.com>

5 files changed, 47 insertions, 6 deletions

diff --git a/.gitlab-ci.d/01-docker/Dockerfile b/.gitlab-ci.d/01-docker/Dockerfile
index ef57661..ac01b89 100644
--- a/.gitlab-ci.d/01-docker/Dockerfile
+++ b/.gitlab-ci.d/01-docker/Dockerfile
@@ -96,6 +96,8 @@ RUN ${APT_UPDATE} \
 # should use the same cache layers, so in the end it makes the collective image
 # size smaller.
 FROM base AS windows-base
+ARG LLVM_MINGW_RELEASE=20240619
+ARG LLVM_MINGW_VARIANT=llvm-mingw-${LLVM_MINGW_RELEASE}-msvcrt-ubuntu-20.04-x86_64
 RUN dpkg --add-architecture i386 \
     && ${APT_UPDATE} \
     && ${APT_INSTALL} \
@@ -106,7 +108,13 @@ RUN dpkg --add-architecture i386 \
         wine \
         wine32 \
         wine64 \
+        wget \
     && ${APT_CLEANUP} \
+    # Install llvm-mingw.
+    && cd /opt \
+    && wget https://github.com/mstorsjo/llvm-mingw/releases/download/${LLVM_MINGW_RELEASE}/${LLVM_MINGW_VARIANT}.tar.xz \
+    && tar -xf ${LLVM_MINGW_VARIANT}.tar.xz \
+    && rm -f ${LLVM_MINGW_VARIANT}.tar.xz \
     # Inspired by https://code.videolan.org/videolan/docker-images
     && wine wineboot --init \
     && while pgrep wineserver > /dev/null; do \
@@ -114,6 +122,7 @@ RUN dpkg --add-architecture i386 \
         sleep 1; \
     done \
     && rm -rf /tmp/wine-*
+ENV PATH=${PATH}:/opt/${LLVM_MINGW_VARIANT}/bin
 
 FROM windows-base AS windows-686
 FROM windows-base AS windows-amd64
diff --git a/.gitlab-ci.d/02-build.yml b/.gitlab-ci.d/02-build.yml
index 86f1e09..c6fb235 100644
--- a/.gitlab-ci.d/02-build.yml
+++ b/.gitlab-ci.d/02-build.yml
@@ -85,14 +85,11 @@ include:
     inputs:
       target: linux-riscv64
       qemu_cpu: rv64,v=true,vext_spec=v1.0,vlen=256,elen=64
-  # Windows targets don't directly support LLVM at this moment.
   - local: .gitlab-ci.d/templates/build.yml
     inputs:
       target: windows-686
-      toolchain: [gnu]
       enable_gnu_coverage: false
   - local: .gitlab-ci.d/templates/build.yml
     inputs:
       target: windows-amd64
-      toolchain: [gnu]
       enable_gnu_coverage: false
diff --git a/.gitlab-ci.d/03-test.yml b/.gitlab-ci.d/03-test.yml
index 1b352af..ee144d8 100644
--- a/.gitlab-ci.d/03-test.yml
+++ b/.gitlab-ci.d/03-test.yml
@@ -154,11 +154,9 @@ include:
         - rv64,v=true,vext_spec=v1.0,vlen=256,elen=64
         - rv64,v=true,vext_spec=v1.0,vlen=512,elen=64
         - rv64,v=true,vext_spec=v1.0,vlen=1024,elen=64
-  # For now, only GNU toolchain is supported for Windows.
   - local: .gitlab-ci.d/templates/test.yml
     inputs:
       target: windows-686
-      toolchain: [gnu]
       pixman_disable:
         # The same as for linux-386.
         - "sse2 ssse3"
@@ -167,7 +165,6 @@ include:
   - local: .gitlab-ci.d/templates/test.yml
     inputs:
       target: windows-amd64
-      toolchain: [gnu]
       pixman_disable:
         # The same as for linux-amd64.
         - ""
diff --git a/.gitlab-ci.d/meson-cross/windows-686-llvm.meson b/.gitlab-ci.d/meson-cross/windows-686-llvm.meson
new file mode 100644
index 0000000..5c81322
--- /dev/null
+++ b/.gitlab-ci.d/meson-cross/windows-686-llvm.meson
@@ -0,0 +1,18 @@
+[binaries]
+c = 'i686-w64-mingw32-clang'
+ar = 'i686-w64-mingw32-llvm-ar'
+strip = 'i686-w64-mingw32-strip'
+windres = 'i686-w64-mingw32-windres'
+exe_wrapper = 'wine'
+
+[built-in options]
+c_link_args = ['-static']
+
+[project options]
+openmp = 'disabled'
+
+[host_machine]
+system = 'windows'
+cpu_family = 'x86'
+cpu = 'i686'
+endian = 'little'
diff --git a/.gitlab-ci.d/meson-cross/windows-amd64-llvm.meson b/.gitlab-ci.d/meson-cross/windows-amd64-llvm.meson
new file mode 100644
index 0000000..8f353fc
--- /dev/null
+++ b/.gitlab-ci.d/meson-cross/windows-amd64-llvm.meson
@@ -0,0 +1,20 @@
+[binaries]
+c = 'x86_64-w64-mingw32-clang'
+ar = 'x86_64-w64-mingw32-llvm-ar'
+strip = 'x86_64-w64-mingw32-strip'
+windres = 'x86_64-w64-mingw32-windres'
+exe_wrapper = 'wine'
+
+[built-in options]
+# Static linking is a workaround around `libwinpthread-1` not being discovered correctly.
+c_link_args = ['-static']
+
+[project options]
+# OpenMP is disabled as it is not being discovered correctly during tests.
+openmp = 'disabled'
+
+[host_machine]
+system = 'windows'
+cpu_family = 'x86_64'
+cpu = 'x86_64'
+endian = 'little'