Update Perl warning suppressions for Clang

Perl XS code generates a lot of warnings. Some additional Clang
warnings now need to be suppressed.

Author: rra

Makefile.am

@@ -341,15 +341,16 @@ distclean-local: clean-local
 	    python/tests/__pycache__
 
 # Suppress some warnings for Perl, PHP, Python, and Ruby code because the
-# auto-generated code otherwise generates them.  This suppression list
-# covers both GCC and Clang.
+# auto-generated code otherwise generates them. This suppression list covers
+# both GCC and Clang.
 PERL_WARNINGS = -Wno-write-strings -Wno-nested-externs			\
 	-Wno-strict-prototypes -Wno-missing-declarations		\
 	-Wno-missing-prototypes -Wno-redundant-decls -Wno-shadow	\
 	-Wno-old-style-definition -Wno-conversion			\
 	-Wno-gnu-statement-expression -Wno-cast-align -Wno-comma	\
 	-Wno-covered-switch-default -Wno-extra-semi-stmt		\
-	-Wno-implicit-fallthrough
+	-Wno-implicit-fallthrough -Wno-declaration-after-statement	\
+	-Wno-switch-enum -Wno-bad-function-cast
 PHP_WARNINGS = -Wno-strict-prototypes -Wno-write-strings		\
 	-Wno-missing-prototypes -Wno-unused-parameter -Wno-sign-compare	\
 	-Wno-redundant-decls -Wno-old-style-definition -Wno-float-equal	\