build: invert default for header checks

In the end the build time is always almost the same, but it's a pain to
change one header and have it check the world. CI continues to use the
check so we can get any mistake before merging.

Tools/ardupilotwaf/ap_library.py

@@ -199,7 +199,7 @@ def ap_library_register_for_check(self):
     if not hasattr(self, 'compiled_tasks'):
         return
 
-    if self.env.DISABLE_HEADER_CHECKS:
+    if not self.env.ENABLE_HEADER_CHECKS:
         return
 
     for t in self.compiled_tasks:

Tools/scripts/build_ci.sh

@@ -113,7 +113,11 @@ for t in $CI_BUILD_TARGET; do
 
     if [[ -n ${waf_supported_boards[$t]} && -z ${CI_CRON_JOB+1} ]]; then
         echo "Starting waf build for board ${t}..."
-        $waf configure --board $t --enable-benchmarks --check-c-compiler="$c_compiler" --check-cxx-compiler="$cxx_compiler"
+        $waf configure --board $t \
+                --enable-benchmarks \
+                --enable-header-checks \
+                --check-c-compiler="$c_compiler" \
+                --check-cxx-compiler="$cxx_compiler"
         $waf clean
         $waf all
         ccache -s && ccache -z

wscript

@@ -81,9 +81,9 @@ option disables that.
 submodules at specific revisions.
 ''')
 
-    g.add_option('--disable-header-checks', action='store_true',
+    g.add_option('--enable-header-checks', action='store_true',
         default=False,
-        help="Disable checking of headers")
+        help="Enable checking of headers")
 
     g.add_option('--default-parameters',
         default=None,
@@ -218,11 +218,11 @@ def configure(cfg):
         cfg.msg('Setting rsync destination to', cfg.options.rsync_dest)
         cfg.env.RSYNC_DEST = cfg.options.rsync_dest
 
-    if cfg.options.disable_header_checks:
-        cfg.msg('Disabling header checks', cfg.options.disable_header_checks)
-        cfg.env.DISABLE_HEADER_CHECKS = True
+    if cfg.options.enable_header_checks:
+        cfg.msg('Enabling header checks', cfg.options.enable_header_checks)
+        cfg.env.ENABLE_HEADER_CHECKS = True
     else:
-        cfg.env.DISABLE_HEADER_CHECKS = False
+        cfg.env.ENABLE_HEADER_CHECKS = False
 
     # TODO: Investigate if code could be changed to not depend on the
     # source absolute path.