valgrind: Add and use valgrind suppressions

data/valgrind.suppressions

+# Fontconfig
+{
+   css_fontconfig_FcPatternCreate
+   Memcheck:Leak
+   match-leak-kinds: definite
+   fun:malloc
+   fun:FcPatternCreate
+   ...
+   fun:XML_ParseBuffer
+   ...
+   fun:gtk_label_get_preferred_layout_size
+   fun:gtk_label_get_preferred_size
+   fun:gtk_label_measure
+   fun:gtk_css_custom_gadget_get_preferred_size
+   fun:gtk_css_gadget_get_preferred_size
+   ...
+}
+
+{
+   css_fontconfig_FcFontRenderPrepare
+   Memcheck:Leak
+   match-leak-kinds: definite
+   fun:realloc
+   ...
+   fun:FcFontRenderPrepare
+   fun:FcFontMatch
+   ...
+   fun:gtk_css_custom_gadget_get_preferred_size
+   fun:gtk_css_gadget_get_preferred_size
+   ...
+}
+
+{
+   fontconfig_malloc
+   Memcheck:Leak
+   match-leak-kinds: definite
+   fun:malloc
+   obj:/usr/lib/*/libfontconfig.so.*
+   ...
+}
+
+{
+   fontconfig_realloc
+   Memcheck:Leak
+   match-leak-kinds: definite
+   fun:realloc
+   obj:/usr/lib/*/libfontconfig.so.*
+   ...
+}

meson.build

@@ -62,6 +62,7 @@ add_project_arguments(
 
 run_data = configuration_data()
 run_data.set('ABS_BUILDDIR', meson.current_build_dir())
+run_data.set('ABS_SRCDIR', meson.current_source_dir())
 configure_file(
   input: 'run.in',
   output: 'run',

run.in

 #!/bin/sh
 set -e
 
+ABS_BUILDDIR='@ABS_BUILDDIR@'
+ABS_SRCDIR='@ABS_SRCDIR@'
 
 if [ "${PHOSH_VALGRIND}" = 1 ]; then
    echo "Running phosh under valgrind"
-   WRAPPER="valgrind --tool=memcheck --leak-check=full --leak-resolution=high --num-callers=30 --log-file=vgdump"
+   WRAPPER="valgrind -v              \
+           --tool=memcheck           \
+           --leak-check=full         \
+           --leak-resolution=high    \
+           --num-callers=30          \
+           --log-file=vgdump         \
+           --suppressions=${ABS_SRCDIR}/data/valgrind.suppressions \
+   "
 fi
 
-ABS_BUILDDIR='@ABS_BUILDDIR@'
-
 # Start up g-s-d, etc.
 gnome-session --session=gnome-dummy --disable-acceleration-check &