[libxml2] Enable continuous integration via GitLab CI

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 61f2abb1f31e8f638c0059d631c064994add71e0
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Fri Oct 4 00:21:24 2019 +0200

    Enable continuous integration via GitLab CI
    
    Port the Travis CI setup to GitLab. We currently run three builds:
    
    - GCC with -std=c89
    - clang with ASan and UBSan
    - clang with MSan
    
    Closes #110.

 .gitlab-ci.yml | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
new file mode 100644
index 00000000..515cb307
--- /dev/null
+++ b/.gitlab-ci.yml
@@ -0,0 +1,38 @@
+default:
+  # The image was generated with the following Dockerfile:
+  #
+  # FROM ubuntu:19.04
+  # RUN apt-get update && \
+  #     apt-get upgrade -y && \
+  #     apt-get install -y --no-install-recommends \
+  #         autoconf automake libtool pkg-config \
+  #         gcc clang make \
+  #         python-dev zlib1g-dev liblzma-dev
+  image: registry.gitlab.gnome.org/gnome/libxml2
+
+.test:
+  script:
+    - sh autogen.sh $CONFIG
+    - make -j$(nproc) V=1
+    - make check
+
+gcc:
+  extends: .test
+  variables:
+    CFLAGS: "-O2 -std=c89 -D_XOPEN_SOURCE=700 -Werror"
+
+clang:asan:
+  extends: .test
+  variables:
+    CONFIG: "--without-python"
+    CC: clang
+    CFLAGS: "-O2 -g -fno-omit-frame-pointer -fsanitize=address,undefined -fno-sanitize=pointer-overflow 
-fno-sanitize-recover=all -Werror -Wno-error=cast-align"
+    UBSAN_OPTIONS: "print_stacktrace=1"
+
+clang:msan:
+  extends: .test
+  variables:
+    CONFIG: "--without-python --without-zlib --without-lzma"
+    CC: clang
+    CFLAGS: "-O2 -g -fno-omit-frame-pointer -fsanitize=memory -Werror -Wno-error=cast-align"
+