diff --git a/tools/perf/jvmti/Build b/tools/perf/jvmti/Build
index 1e148bbdf820..202cadaaf097 100644
--- a/tools/perf/jvmti/Build
+++ b/tools/perf/jvmti/Build
@@ -2,7 +2,7 @@ jvmti-y += libjvmti.o
 jvmti-y += jvmti_agent.o
 
 # For strlcpy
-jvmti-y += libstring.o
+jvmti-y += libstring.o libctype.o
 
 CFLAGS_jvmti         = -fPIC -DPIC -I$(JDIR)/include -I$(JDIR)/include/linux
 CFLAGS_REMOVE_jvmti  = -Wmissing-declarations
@@ -15,3 +15,7 @@ CFLAGS_libstring.o += -Wno-unused-parameter -DETC_PERFCONFIG="BUILD_STR($(ETC_PE
 $(OUTPUT)jvmti/libstring.o: ../lib/string.c FORCE
 	$(call rule_mkdir)
 	$(call if_changed_dep,cc_o_c)
+
+$(OUTPUT)jvmti/libctype.o: ../lib/ctype.c FORCE
+	$(call rule_mkdir)
+	$(call if_changed_dep,cc_o_c)