--- detex-src/detex.l	(revision 64397)
+++ detex-src/detex.l	(working copy)
@@ -110,7 +110,10 @@
 #define STRIPARGS(x)	cArgs=x; LaBEGIN LaMacro2
 #define	CITE(x)		if (fLatex && !fCite) KILLARGS(x)
 
+/* avoid gratuitous gcc warning from passing -D for this on command line */
+#ifndef NO_MALLOC_DECL
 #define NO_MALLOC_DECL
+#endif
 
 void LineBreak();
 void Ignore();
