configure: Honour --disable-werror for Sphinx

If we are not making warnings fatal for compilation, make them
non-fatal when building the Sphinx documentation also.  (For instance
Sphinx 3.0 warns about some constructs that older versions were happy
with, which is a build failure if we use the warnings-as-errors
flag.)

This provides a workaround at least for LP:1872113.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200411182934.28678-2-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

1 files changed, 8 insertions, 1 deletions

diff --git a/configure b/configure
index 233c671aaa..9b1f5b33e4 100755
--- a/configure
+++ b/configure
@@ -4928,6 +4928,12 @@ if check_include sys/kcov.h ; then
     kcov=yes
 fi
 
+# If we're making warnings fatal, apply this to Sphinx runs as well
+sphinx_werror=""
+if test "$werror" = "yes"; then
+    sphinx_werror="-W"
+fi
+
 # Check we have a new enough version of sphinx-build
 has_sphinx_build() {
     # This is a bit awkward but works: create a trivial document and
@@ -4936,7 +4942,7 @@ has_sphinx_build() {
     # sphinx-build doesn't exist at all or if it is too old.
     mkdir -p "$TMPDIR1/sphinx"
     touch "$TMPDIR1/sphinx/index.rst"
-    "$sphinx_build" -c "$source_path/docs" -b html "$TMPDIR1/sphinx" "$TMPDIR1/sphinx/out" >/dev/null 2>&1
+    "$sphinx_build" $sphinx_werror -c "$source_path/docs" -b html "$TMPDIR1/sphinx" "$TMPDIR1/sphinx/out" >/dev/null 2>&1
 }
 
 # Check if tools are available to build documentation.
@@ -7631,6 +7637,7 @@ echo "INSTALL_PROG=$install -c -m 0755" >> $config_host_mak
 echo "INSTALL_LIB=$install -c -m 0644" >> $config_host_mak
 echo "PYTHON=$python" >> $config_host_mak
 echo "SPHINX_BUILD=$sphinx_build" >> $config_host_mak
+echo "SPHINX_WERROR=$sphinx_werror" >> $config_host_mak
 echo "GENISOIMAGE=$genisoimage" >> $config_host_mak
 echo "CC=$cc" >> $config_host_mak
 if $iasl -h > /dev/null 2>&1; then