Don't drop -Wall in the swig Perl bindings, otherwise building with
e.g. -Wformat-security might break.
https://bugzilla.redhat.com/show_bug.cgi?id=1037341
--- subversion-1.8.5/subversion/bindings/swig/perl/native/Makefile.PL.in.swigplWall
+++ subversion-1.8.5/subversion/bindings/swig/perl/native/Makefile.PL.in
@@ -54,7 +54,6 @@ my $includes = ' -I/usr/include/apr-1
# SWIG is using C++ style comments in an extern "C" code.
$cflags =~ s/-ansi\s+//g;
$cflags =~ s/-std=c89\s+//g;
-$cflags =~ s/-Wall//g;
$cflags =~ s/-Wunused//g;
$cflags =~ s/-Wshadow//g;
$cflags =~ s/-Wstrict-prototypes//g;