add CUNKNOWN make variables to entry Makefiles

1990/theorem/Makefile

@@ -45,9 +45,13 @@ CSILENCE= -Wno-deprecated-declarations -Wno-empty-body -Wno-error -Wno-unused-va
 	  -Wno-deprecated-non-prototype -Wno-int-conversion -Wno-strict-prototypes \
 	  -Wno-implicit-int
 
+# Attempt to silence unknown warnings
+#
+CUNKNOWN= -Wno-unknown-warning-option
+
 # Common C compiler warning flags
 #
-CWARN= -Wall -Wextra -pedantic ${CSILENCE}
+CWARN= -Wall -Wextra ${CSILENCE} ${CUNKNOWN}
 
 # Compiler standard
 #
@@ -55,9 +59,6 @@ CSTD= -std=gnu90
 
 # Compiler bit architecture
 #
-# Some entries require 32-bitness: ARCH= -m32
-# Some entries require 64-bitness: ARCH= -m64
-#
 ARCH=
 
 # Defines that are needed to compile