[dconf/fix/build: 2/3] gsettings: Update abicheck.sh script

[Daniel Playfair Cal <danielplayfaircal src gnome org>]

commit 4723747667cef384c8da48da9546d430b5a69de3
Author: Diego Escalante Urrelo <diegoe gnome org>
Date:   Thu Oct 31 07:01:11 2019 -0500

    gsettings: Update abicheck.sh script
    
    gcc-9 is including `mangle_path` in the symbols of
    gsettings/libdconfsettings.so when building with support for gcov
    (--coverage). This means that our ignored symbols had to be updated.
    
    Update abicheck.sh so the test suite passes again. Also include a
    comment to explain the above and how the test works.
    
    Fixes: https://gitlab.gnome.org/GNOME/dconf/issues/60

 gsettings/abicheck.sh | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)
---
diff --git a/gsettings/abicheck.sh b/gsettings/abicheck.sh
index c8b072b..1dca6ea 100755
--- a/gsettings/abicheck.sh
+++ b/gsettings/abicheck.sh
@@ -1,4 +1,26 @@
 #!/bin/sh
 
+# The following checks that gsettings/libdconfsettings.so only has
+# dconf_* symbols.
+#
+# We also make sure to ignore gcov symbols included when building with
+# --coverage, which usually means the following:
+#
+# __gcov_error_file
+# __gcov_master
+# __gcov_sort_n_vals
+# __gcov_var
+#
+# And starting with gcc-9, also this one:
+#
+# mangle_path
+
 ${NM:-nm} --dynamic --defined-only $GSETTINGS_LIB > public-abi
-test "`cat public-abi | cut -f 3 -d ' ' | grep -v ^_ | grep -v ^g_io_module | wc -l`" -eq 0 && rm public-abi
+
+test "`\
+    cat public-abi | \
+    cut -f 3 -d ' ' | \
+    grep -v ^_ | \
+    grep -v ^mangle_path | \
+    grep -v ^g_io_module | \
+    wc -l`" -eq 0 && rm public-abi