diff --git a/mozilla/tools/trace-malloc/Makefile.in b/mozilla/tools/trace-malloc/Makefile.in
index 9768a0186f8..788b48c3e41 100644
--- a/mozilla/tools/trace-malloc/Makefile.in
+++ b/mozilla/tools/trace-malloc/Makefile.in
@@ -53,6 +53,10 @@ SIMPLECSRCS	+= \
 		tmstats.c \
 		$(NULL)
 
+# Set CPP_PROG_LINK manually since we're using SIMPLECPPSRCS rather than
+# CPPSRCS.
+CPP_PROG_LINK	= 1
+
 SIMPLECPPSRCS	= \
 		leaksoup.cpp \
 		$(NULL)