diff --git a/Makefile b/Makefile
index f1f4f1396..499239fd9 100644
--- a/Makefile
+++ b/Makefile
@@ -131,6 +131,7 @@ SUBDIR += tests/pcre-flags
 SUBDIR += tests/pcre-repeat
 SUBDIR += tests/pred
 SUBDIR += tests/re_literal
+SUBDIR += tests/re_strings
 SUBDIR += tests/reverse
 SUBDIR += tests/trim
 SUBDIR += tests/union
diff --git a/include/fsm/fsm.h b/include/fsm/fsm.h
index 7c3883749..2b4c438f1 100644
--- a/include/fsm/fsm.h
+++ b/include/fsm/fsm.h
@@ -207,6 +207,12 @@ fsm_setend(struct fsm *fsm, fsm_state_t state, int end);
 int
 fsm_setendid(struct fsm *fsm, fsm_end_id_t id);
 
+/* Associate a numeric ID with a specific end state in an fsm.
+ * Returns 1 on success, 0 on error.
+ * */
+int
+fsm_setendidstate(struct fsm *fsm, fsm_state_t end_state, fsm_end_id_t id);
+
 /* Get the end IDs associated with an end state, if any.
  * If id_buf has enough cells to store all the end IDs (according
  * to id_buf_count) then they are written into id_buf[] and
diff --git a/include/re/strings.h b/include/re/strings.h
index 06387a54c..fe4f7adc2 100644
--- a/include/re/strings.h
+++ b/include/re/strings.h
@@ -7,7 +7,7 @@
 #ifndef RE_STRINGS_H
 #define RE_STRINGS_H
 
-struct fsm;
+#include <fsm/fsm.h>
 struct fsm_options;
 
 struct re_strings;
@@ -42,10 +42,10 @@ void
 re_strings_free(struct re_strings *g);
 
 int
-re_strings_add_raw(struct re_strings *g, const void *p, size_t n);
+re_strings_add_raw(struct re_strings *g, const void *p, size_t n, const fsm_end_id_t *endid);
 
 int
-re_strings_add_str(struct re_strings *g, const char *s);
+re_strings_add_str(struct re_strings *g, const char *s, const fsm_end_id_t *endid);
 
 struct fsm *
 re_strings_build(struct re_strings *g,
diff --git a/src/libfsm/endids.c b/src/libfsm/endids.c
index 444ccbc2e..1fc98ae68 100644
--- a/src/libfsm/endids.c
+++ b/src/libfsm/endids.c
@@ -84,6 +84,16 @@ fsm_setendid(struct fsm *fsm, fsm_end_id_t id)
 	return 1;
 }
 
+int
+fsm_setendidstate(struct fsm *fsm, fsm_state_t end_state, fsm_end_id_t id)
+{
+	enum fsm_endid_set_res sres = fsm_endid_set(fsm, end_state, id);
+	if (sres == FSM_ENDID_SET_ERROR_ALLOC_FAIL) {
+		return 0;
+	}
+	return 1;
+}
+
 enum fsm_getendids_res
 fsm_getendids(const struct fsm *fsm, fsm_state_t end_state,
     size_t id_buf_count, fsm_end_id_t *id_buf,
diff --git a/src/libfsm/libfsm.syms b/src/libfsm/libfsm.syms
index 415bffbea..a2570b8c9 100644
--- a/src/libfsm/libfsm.syms
+++ b/src/libfsm/libfsm.syms
@@ -89,6 +89,7 @@ fsm_getendids
 fsm_setendid
 fsm_mapendids
 fsm_increndids
+fsm_setendidstate
 
 fsm_countedges
 fsm_countstates
diff --git a/src/libre/ac.c b/src/libre/ac.c
index 2ebdb4f7e..efe13df36 100644
--- a/src/libre/ac.c
+++ b/src/libre/ac.c
@@ -13,6 +13,7 @@
 #include <ctype.h>
 
 #include <fsm/fsm.h>
+#include <adt/stateset.h>
 
 #include "ac.h"
 
@@ -21,6 +22,9 @@ enum { POOL_BLOCK_SIZE = 256 };
 struct trie_state {
 	struct trie_state *children[256];
 	struct trie_state *fail;
+	/* use a state set as an endid set */
+	struct state_set *endids;
+
 	fsm_state_t st;
 	unsigned int index;
 	unsigned int output:1;
@@ -73,6 +77,7 @@ newstate(struct trie_graph *g)
 	st->index   = ++g->nstates;
 
 	st->output  = 0;
+	st->endids  = NULL;
 
 	return st;
 }
@@ -86,6 +91,10 @@ cleanup_pool(struct trie_graph *g)
 		p = g->pool;
 		g->pool = p->next;
 
+		for (size_t i = 0; i < p->n; i++) {
+			state_set_free(p->states[i].endids);
+		}
+
 		free(p->states);
 		free(p);
 	}
@@ -126,7 +135,7 @@ trie_create(void)
 }
 
 struct trie_graph *
-trie_add_word(struct trie_graph *g, const char *w, size_t n)
+trie_add_word(struct trie_graph *g, const char *w, size_t n, const fsm_end_id_t *endid)
 {
 	struct trie_state *st;
 	size_t i;
@@ -159,6 +168,9 @@ trie_add_word(struct trie_graph *g, const char *w, size_t n)
 		g->depth = n;
 	}
 
+	if (endid != NULL) {
+		state_set_add(&st->endids, NULL, (fsm_state_t)*endid);
+	}
 	return g;
 }
 
@@ -278,7 +290,7 @@ trie_to_fsm_state(struct trie_state *ts, struct fsm *fsm,
 	assert(fsm != NULL);
 	assert(q != NULL);
 
-	if (ts->output && have_end) {
+	if (ts->output && have_end && state_set_empty(ts->endids)) {
 		*q = single_end;
 		return 1;
 	}
@@ -315,6 +327,16 @@ trie_to_fsm_state(struct trie_state *ts, struct fsm *fsm,
 
 	if (ts->output) {
 		fsm_setend(fsm, st, 1);
+
+		struct state_iter si;
+		fsm_state_t state;
+		state_set_reset(ts->endids, &si);
+		while (state_set_next(&si, &state)) {
+			fsm_end_id_t endid = (fsm_end_id_t)state;
+			if (!fsm_setendidstate(fsm, st, endid)) {
+				return 0;
+			}
+		}
 	}
 
 	*q = st;
diff --git a/src/libre/ac.h b/src/libre/ac.h
index 480c76bfb..edabca27c 100644
--- a/src/libre/ac.h
+++ b/src/libre/ac.h
@@ -7,6 +7,8 @@
 #ifndef AC_H
 #define AC_H
 
+#include "fsm/fsm.h"
+
 struct fsm;
 struct fsm_state;
 struct fsm_options;
@@ -20,7 +22,8 @@ void
 trie_free(struct trie_graph *g);
 
 struct trie_graph *
-trie_add_word(struct trie_graph *g, const char *w, size_t n);
+trie_add_word(struct trie_graph *g, const char *w, size_t n,
+	const fsm_end_id_t *endid);
 
 int
 trie_add_failure_edges(struct trie_graph *g);
diff --git a/src/libre/re_strings.c b/src/libre/re_strings.c
index 06b7dc772..b2f04fec1 100644
--- a/src/libre/re_strings.c
+++ b/src/libre/re_strings.c
@@ -32,7 +32,7 @@ re_strings(const struct fsm_options *opt, const char *a[], size_t n,
 	}
 
 	for (i = 0; i < n; i++) {
-		if (!re_strings_add_str(g, a[i])) {
+		if (!re_strings_add_str(g, a[i], NULL)) {
 			goto error;
 		}
 	}
@@ -64,20 +64,20 @@ re_strings_free(struct re_strings *g)
 }
 
 int
-re_strings_add_raw(struct re_strings *g, const void *p, size_t n)
+re_strings_add_raw(struct re_strings *g, const void *p, size_t n, const fsm_end_id_t *endid)
 {
 	assert(p != NULL);
 	assert(n > 0);
 
-	return trie_add_word((struct trie_graph *) g, p, n) != NULL;
+	return trie_add_word((struct trie_graph *) g, p, n, endid) != NULL;
 }
 
 int
-re_strings_add_str(struct re_strings *g, const char *s)
+re_strings_add_str(struct re_strings *g, const char *s, const fsm_end_id_t *endid)
 {
 	assert(s != NULL);
 
-	return re_strings_add_raw(g, s, strlen(s));
+	return re_strings_add_raw(g, s, strlen(s), endid);
 }
 
 struct fsm *
diff --git a/tests/re_strings/Makefile b/tests/re_strings/Makefile
new file mode 100644
index 000000000..7fc7f2548
--- /dev/null
+++ b/tests/re_strings/Makefile
@@ -0,0 +1,26 @@
+.include "../../share/mk/top.mk"
+
+TEST.tests/re_strings != ls -1 tests/re_strings/re_strings*.c
+TEST_SRCDIR.tests/re_strings = tests/re_strings
+TEST_OUTDIR.tests/re_strings = ${BUILD}/tests/re_strings
+
+.for n in ${TEST.tests/re_strings:T:R:C/^re_strings//}
+test:: ${TEST_OUTDIR.tests/re_strings}/res${n}
+SRC += ${TEST_SRCDIR.tests/re_strings}/re_strings${n}.c
+CFLAGS.${TEST_SRCDIR.tests/re_strings}/re_strings${n}.c = -UNDEBUG
+
+${TEST_OUTDIR.tests/re_strings}/run${n}: ${TEST_OUTDIR.tests/re_strings}/re_strings${n}.o ${TEST_OUTDIR.tests/re_strings}/testutil.o
+	${CC} ${CFLAGS} -o ${TEST_OUTDIR.tests/re_strings}/run${n} ${TEST_OUTDIR.tests/re_strings}/re_strings${n}.o ${TEST_OUTDIR.tests/re_strings}/testutil.o ${BUILD}/lib/libfsm.a ${BUILD}/lib/libre.a
+
+${TEST_OUTDIR.tests/re_strings}/re_strings${n}.o: tests/re_strings/testutil.h
+
+${TEST_OUTDIR.tests/re_strings}/res${n}: ${TEST_OUTDIR.tests/re_strings}/run${n}
+	( ${TEST_OUTDIR.tests/re_strings}/run${n} 1>&2 && echo PASS || echo FAIL ) > ${TEST_OUTDIR.tests/re_strings}/res${n}
+
+.for lib in ${LIB:Mlibfsm} ${LIB:Mlibre}
+${TEST_OUTDIR.tests/re_strings}/run${n}: ${BUILD}/lib/${lib:R}.a
+.endfor
+.endfor
+
+${TEST_OUTDIR.tests/re_strings}/testutil.o: tests/re_strings/testutil.c
+	${CC} ${CFLAGS} -c -o ${TEST_OUTDIR.tests/re_strings}/testutil.o tests/re_strings/testutil.c
diff --git a/tests/re_strings/re_strings1.c b/tests/re_strings/re_strings1.c
new file mode 100644
index 000000000..44f10d41d
--- /dev/null
+++ b/tests/re_strings/re_strings1.c
@@ -0,0 +1,21 @@
+#include "testutil.h"
+
+const char *strings[] = {
+	"aa",
+	"ab",
+	"ac",
+	"ba",
+	"bb",
+	"bc",
+	"ca",
+	"cb",
+	"cc",
+	NULL,
+};
+
+int main(int argc, char **argv)
+{
+	(void)argc;
+	(void)argv;
+	return run_test(strings);
+}
diff --git a/tests/re_strings/re_strings2.c b/tests/re_strings/re_strings2.c
new file mode 100644
index 000000000..6e4c80459
--- /dev/null
+++ b/tests/re_strings/re_strings2.c
@@ -0,0 +1,17 @@
+#include "testutil.h"
+
+const char *strings[] = {
+	"first",
+	"duplicate",
+	"duplicate",
+	"duplicate",
+	"last",
+	NULL,
+};
+
+int main(int argc, char **argv)
+{
+	(void)argc;
+	(void)argv;
+	return run_test(strings);
+}
diff --git a/tests/re_strings/re_strings3.c b/tests/re_strings/re_strings3.c
new file mode 100644
index 000000000..3f4f1d052
--- /dev/null
+++ b/tests/re_strings/re_strings3.c
@@ -0,0 +1,15 @@
+#include "testutil.h"
+
+const char *strings[] = {
+	"duplicate",
+	"duplicate",
+	"duplicate",
+	NULL,
+};
+
+int main(int argc, char **argv)
+{
+	(void)argc;
+	(void)argv;
+	return run_test(strings);
+}
diff --git a/tests/re_strings/re_strings4.c b/tests/re_strings/re_strings4.c
new file mode 100644
index 000000000..b1e00e70f
--- /dev/null
+++ b/tests/re_strings/re_strings4.c
@@ -0,0 +1,13 @@
+#include "testutil.h"
+
+const char *strings[] = {
+	/* empty */
+	NULL,
+};
+
+int main(int argc, char **argv)
+{
+	(void)argc;
+	(void)argv;
+	return run_test(strings);
+}
diff --git a/tests/re_strings/testutil.c b/tests/re_strings/testutil.c
new file mode 100644
index 000000000..4f4678b0d
--- /dev/null
+++ b/tests/re_strings/testutil.c
@@ -0,0 +1,71 @@
+#include "testutil.h"
+
+#include <stdbool.h>
+#include <assert.h>
+
+#include "fsm/fsm.h"
+#include "fsm/options.h"
+
+#include "re/re.h"
+#include "re/strings.h"
+
+static struct fsm_options opt;
+
+#define MAX_INPUTS 100
+static fsm_end_id_t id_buf[MAX_INPUTS];
+
+int
+run_test(const char **strings)
+{
+	struct re_strings *s = re_strings_new();
+	assert(s != NULL);
+
+	fsm_end_id_t id = 0;
+	const char **input = strings;
+	while (*input != NULL) {
+		if (!re_strings_add_str(s, *input, &id)) {
+			assert(!"re_strings_add_str");
+		}
+
+		input++;
+		id++;
+		assert(id < MAX_INPUTS);
+	}
+
+	const int flags = 0;	/* not anchored */
+
+	struct fsm *fsm = re_strings_build(s, &opt, flags);
+	assert(fsm != NULL);
+
+	/* Each literal string input should match, and the set of
+	 * matching endids should include the expected one. */
+	id = 0;
+	input = strings;
+	while (*input != NULL) {
+		fsm_state_t end;
+		const char **string = input;
+		const int res = fsm_exec(fsm, fsm_sgetc, string, &end, NULL);
+		assert(res > 0); /* match */
+
+		size_t written;
+		enum fsm_getendids_res eres = fsm_getendids(fsm, end,
+		    MAX_INPUTS, id_buf, &written);
+		assert(eres == FSM_GETENDIDS_FOUND);
+		bool found = false;
+		for (size_t i = 0; i < written; i++) {
+			if (id_buf[i] == id) {
+				found = true;
+				break;
+			}
+		}
+		assert(found);
+
+		input++;
+		id++;
+	}
+
+	re_strings_free(s);
+	fsm_free(fsm);
+
+	return EXIT_SUCCESS;
+}
diff --git a/tests/re_strings/testutil.h b/tests/re_strings/testutil.h
new file mode 100644
index 000000000..6898200b7
--- /dev/null
+++ b/tests/re_strings/testutil.h
@@ -0,0 +1,11 @@
+#ifndef TESTUTIL_H
+#define TESTUTIL_H
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+
+int
+run_test(const char **strings);
+
+#endif