[TravisCI] Add Z3_WARNINGS_AS_ERRORS environment variable to

control the `WARNINGS_AS_ERRORS` CMake option.

contrib/ci/scripts/build_z3_cmake.sh

@@ -20,7 +20,8 @@ set -o pipefail
 : ${DOTNET_BINDINGS?"DOTNET_BINDINGS must be specified"}
 : ${JAVA_BINDINGS?"JAVA_BINDINGS must be specified"}
 : ${USE_LTO?"USE_LTO must be specified"}
-: ${Z3_INSTALL_PREFIX?"Z3_INSTALL_PREFIX"}
+: ${Z3_INSTALL_PREFIX?"Z3_INSTALL_PREFIX must be specified"}
+: ${Z3_WARNINGS_AS_ERRORS?"Z3_WARNINGS_AS_ERRORS must be specified"}
 
 ADDITIONAL_Z3_OPTS=()
 
@@ -120,6 +121,7 @@ cmake \
   -DCMAKE_BUILD_TYPE=${Z3_BUILD_TYPE} \
   -DPYTHON_EXECUTABLE=${PYTHON_EXECUTABLE} \
   -DCMAKE_INSTALL_PREFIX=${Z3_INSTALL_PREFIX} \
+  -DWARNINGS_AS_ERRORS=${Z3_WARNINGS_AS_ERRORS} \
   "${ADDITIONAL_Z3_OPTS[@]}" \
   "${Z3_SRC_DIR}"
 

contrib/ci/scripts/travis_ci_linux_entry_point.sh

@@ -120,6 +120,13 @@ if [ -n "${NO_SUPPRESS_OUTPUT}" ]; then
   )
 fi
 
+if [ -n "${Z3_WARNINGS_AS_ERRORS}" ]; then
+  BUILD_OPTS+=( \
+    "--build-arg" \
+    "Z3_WARNINGS_AS_ERRORS=${Z3_WARNINGS_AS_ERRORS}" \
+  )
+fi
+
 case ${LINUX_BASE} in
   ubuntu_14.04)
     BASE_DOCKER_FILE="${DOCKER_FILE_DIR}/z3_base_ubuntu_14.04.Dockerfile"