The upstream code tries to remove -g from CFLAGS, but the logic also matches
the -g in the middle of flags, like:
-frecord-gcc-switches => -frecordcc-switches
-ggdb3 => ggdb3
Both of which cause GCC to fail horribly!

Fix the grep & sed to only match standalone instances.

Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>

diff -Nuar dante-1.4.0.orig/compiler.m4 dante-1.4.0/compiler.m4
--- dante-1.4.0.orig/compiler.m4	2013-10-24 13:20:23.000000000 -0700
+++ dante-1.4.0/compiler.m4	2014-01-05 15:18:03.544336373 -0800
@@ -375,14 +375,14 @@
 	gcc)
 	    if test x"$aixldbug" != x; then
 	        #disable debug info
-		if echo $CFLAGS | grep -- "-g" >/dev/null; then
-		    CFLAGS="`echo $CFLAGS | sed -e 's/-g//g'`"
+		if echo $CFLAGS | grep -w -- "-g" >/dev/null; then
+		    CFLAGS="`echo $CFLAGS | sed -e 's/\<-g\>//g'`"
 		fi
 		CFLAGS="$CFLAGS${CFLAGS:+ }-g0"
 	    else
 		#use -ggdb also when not debugging
-		if echo $CFLAGS | grep -- "-g" >/dev/null; then
-		    CFLAGS="`echo $CFLAGS | sed -e 's/-g//g'`"
+		if echo $CFLAGS | grep -w -- "-g" >/dev/null; then
+		    CFLAGS="`echo $CFLAGS | sed -e 's/\<-g\>//g'`"
 		fi
 		CFLAGS="$CFLAGS${CFLAGS:+ }-ggdb"
 	    fi