diff --git a/lib/libc/tests/stdio/fmemopen2_test.c b/lib/libc/tests/stdio/fmemopen2_test.c
index d733d10ddb48..c3aa6c54a6f9 100644
--- a/lib/libc/tests/stdio/fmemopen2_test.c
+++ b/lib/libc/tests/stdio/fmemopen2_test.c
@@ -105,10 +105,9 @@ ATF_TC_WITHOUT_HEAD(test_autoalloc);
 ATF_TC_BODY(test_autoalloc, tc)
 {
 	/* Let fmemopen allocate the buffer. */
-	char str[] = "A quick test";
 	FILE *fp;
 	long pos;
-	size_t nofw, nofr, i;
+	size_t nofw, i;
 	int rc;
 
 	/* Open a FILE * using fmemopen. */
diff --git a/lib/libc/tests/stdio/getdelim_test.c b/lib/libc/tests/stdio/getdelim_test.c
index e323250c96b6..ffc6810dd616 100644
--- a/lib/libc/tests/stdio/getdelim_test.c
+++ b/lib/libc/tests/stdio/getdelim_test.c
@@ -113,7 +113,6 @@ ATF_TC_BODY(getline_basic, tc)
 ATF_TC_WITHOUT_HEAD(stream_error);
 ATF_TC_BODY(stream_error, tc)
 {
-	FILE *fp;
 	char *line;
 	size_t linecap;
 
diff --git a/lib/libc/tests/stdio/perror_test.c b/lib/libc/tests/stdio/perror_test.c
index a58121c4bd44..989f1ff6ea59 100644
--- a/lib/libc/tests/stdio/perror_test.c
+++ b/lib/libc/tests/stdio/perror_test.c
@@ -48,7 +48,7 @@ static char tmpfil[PATH_MAX];
 ATF_TC_WITHOUT_HEAD(perror_test);
 ATF_TC_BODY(perror_test, tc)
 {
-	char buf[512], lbuf[512];
+	char lbuf[512];
 	int i;
 	char *s;
 
diff --git a/lib/libc/tests/stdio/scanfloat_test.c b/lib/libc/tests/stdio/scanfloat_test.c
index 60c1b61d06b2..7e27e69542e7 100644
--- a/lib/libc/tests/stdio/scanfloat_test.c
+++ b/lib/libc/tests/stdio/scanfloat_test.c
@@ -58,7 +58,6 @@ ATF_TC_BODY(normalized_numbers, tc)
 	long double ld = 0.0;
 	double d = 0.0;
 	float f = 0.0;
-	char *endp;
 
 	buf[0] = '\0';
 	ATF_REQUIRE(setlocale(LC_NUMERIC, ""));
@@ -157,7 +156,6 @@ ATF_TC_BODY(infinities_and_nans, tc)
 	long double ld = 0.0;
 	double d = 0.0;
 	float f = 0.0;
-	char *endp;
 
 	ATF_REQUIRE(setlocale(LC_NUMERIC, "C"));
 
@@ -205,11 +203,8 @@ ATF_TC_BODY(infinities_and_nans, tc)
 ATF_TC_WITHOUT_HEAD(rounding_tests);
 ATF_TC_BODY(rounding_tests, tc)
 {
-	char buf[128];
 	long double ld = 0.0;
 	double d = 0.0;
-	float f = 0.0;
-	char *endp;
 
 	ATF_REQUIRE(setlocale(LC_NUMERIC, "C"));
 
@@ -287,10 +282,6 @@ ATF_TC_BODY(rounding_tests, tc)
 ATF_TC_WITHOUT_HEAD(strtod);
 ATF_TC_BODY(strtod, tc)
 {
-	char buf[128];
-	long double ld = 0.0;
-	double d = 0.0;
-	float f = 0.0;
 	char *endp;
 
 	ATF_REQUIRE(setlocale(LC_NUMERIC, "C"));