add m4 to build via dragonegg and update gcov and memopt m4

m4/dragonegg.m4

@@ -6,12 +6,11 @@ AC_DEFUN([AC_DRAGONEGG],
 		[use_dragonegg=$enableval],
 		[use_dragonegg=no])
 
-	if test "x$use_dragonegg" = "xyes"; then
-	  # this could be more elaborated in finding drageonegg, etc.
+	AS_IF([test "x$enable_dragonegg" = "xyes"], [
 		AC_MSG_NOTICE("using dragonegg gcc plugin")
 		DRAGONEGG_FLAGS="-fplugin=/usr/lib64/llvm/dragonegg.so"
 		AC_SUBST(DRAGONEGG_FLAGS)
-	fi
+	])
 ])
 
 # vim: set ft=m4 ts=2 sw=2:

m4/gcov.m4

@@ -71,6 +71,9 @@ AC_DEFUN([AC_TDD_GCOV],
   COVERAGE_CFLAGS="-O0 -fprofile-arcs -ftest-coverage"
   COVERAGE_CXXFLAGS="-O0 -fprofile-arcs -ftest-coverage"	
   COVERAGE_LDFLAGS="-lgcov"
+  AC_SUBST(COVERAGE_CFLAGS)
+  AC_SUBST(COVERAGE_CXXFLAGS)
+  AC_SUBST(COVERAGE_LDFLAGS)
 
 fi
 ]) # AC_TDD_GCOV

m4/memopt.m4

@@ -1,16 +1,14 @@
 AC_DEFUN([AC_MEM_OPT],
 [
 	AC_ARG_ENABLE(mem_opt,
-		AC_HELP_STRING([--enable-mem-opt],
-		               [enable best bit tree based memory optimizations]),
-		[use_mem_opt=$enableval],
-		[use_mem_opt=no])
+		AC_HELP_STRING([--disable-mem-opt],
+		               [disable best bit tree based memory optimizations]))
 
-	if test "x$use_mem_opt" = "xyes"; then
+	AS_IF([test "x$enable_mem_opt" != "xno"], [
 		AC_MSG_NOTICE("Using best fit tree based memory optimizations")
 		MEM_OPT_FLAGS="-DMEM_OPT"
 		AC_SUBST(MEM_OPT_FLAGS)
-	fi
+	])
 ])
 
 # vim: set ft=m4 ts=2 sw=2: