diff -ru a/src/cap-ng.c b/src/cap-ng.c

--- a/src/cap-ng.c

+++ b/src/cap-ng.c

@@ -46,7 +46,7 @@

 #endif

 # define hidden __attribute__ ((visibility ("hidden")))

-int last_cap hidden = -1;

+unsigned int last_cap hidden = 0;

 /*

  * Some milestones of when things became available:

  * 2.6.24 kernel	XATTR_NAME_CAPS

@@ -65,7 +65,7 @@

 // Local defines

 #define MASK(x) (1U << (x))

 #ifdef PR_CAPBSET_DROP

-#define UPPER_MASK ~(unsigned)((~0U)<<(last_cap-31))

+#define UPPER_MASK ~((~0U)<<(last_cap-31))

 #else

 // For v1 systems UPPER_MASK will never be used

 #define UPPER_MASK (unsigned)(~0U)

@@ -73,7 +73,7 @@

 // Re-define cap_valid so its uniform between V1 and V3

 #undef cap_valid

-#define cap_valid(x) ((x) <= (unsigned int)last_cap)

+#define cap_valid(x) ((x) <= last_cap)

 // If we don't have the xattr library, then we can't

 // compile-in file system capabilities

@@ -174,6 +174,26 @@

 #ifdef HAVE_PTHREAD_H

 	pthread_atfork(NULL, NULL, deinit);

 #endif

+	// Detect last cap

+	if (last_cap == 0) {

+		int fd;

+

+		fd = open("/proc/sys/kernel/cap_last_cap", O_RDONLY);

+		if (fd >= 0) {

+			char buf[8];

+			int num = read(fd, buf, sizeof(buf) - 1);

+			if (num > 0) {

+				buf[num] = 0;

+				errno = 0;

+				unsigned int val = strtoul(buf, NULL, 10);

+				if (errno == 0)

+					last_cap = val;

+			}

+			close(fd);

+		}

+		if (last_cap == 0)

+			last_cap = CAP_LAST_CAP;

+	}

 }

 static void init(void)

@@ -199,26 +219,6 @@

 #else

 	m.hdr.pid = (unsigned)getpid();

 #endif

-	// Detect last cap

-	if (last_cap == -1) {

-		int fd;

-

-		fd = open("/proc/sys/kernel/cap_last_cap", O_RDONLY);

-		if (fd >= 0) {

-			char buf[8];

-			int num = read(fd, buf, sizeof(buf) - 1);

-			if (num > 0) {

-				buf[num] = 0;

-				errno = 0;

-				int val = strtoul(buf, NULL, 10);

-				if (errno == 0)

-					last_cap = val;

-			}

-			close(fd);

-		}

-		if (last_cap == -1)

-			last_cap = CAP_LAST_CAP;

-	}

 	m.state = CAPNG_ALLOCATED;

 }

@@ -478,7 +478,7 @@

 		if (CAPNG_INHERITABLE & type)

 			v1_update(action, capability, &m.data.v1.inheritable);

 	} else {

-		int idx;

+		unsigned int idx;

 		if (capability > 31) {

 			idx = capability>>5;

@@ -545,7 +545,7 @@

 		memcpy(&state, &m, sizeof(state)); /* save state */

 		capng_get_caps_process();

 		if (capng_have_capability(CAPNG_EFFECTIVE, CAP_SETPCAP)) {

-			int i;

+			unsigned int i;

 			memcpy(&m, &state, sizeof(m)); /* restore state */

 			rc = 0;

 			for (i=0; i <= last_cap && rc == 0; i++)

@@ -602,7 +602,7 @@

 #ifndef VFS_CAP_U32

 	return -1;

 #else

-	int rc, size;

+	int rc, size = 0;

 	struct vfs_cap_data filedata;

 	struct stat buf;

@@ -1010,7 +1010,7 @@

 char *capng_print_caps_text(capng_print_t where, capng_type_t which)

 {

-	int i, once = 0, cnt = 0;

+	unsigned int i, once = 0, cnt = 0;

 	char *ptr = NULL;

 	if (m.state < CAPNG_INIT)

diff -ru a/src/lookup_table.c b/src/lookup_table.c

--- a/src/lookup_table.c

+++ b/src/lookup_table.c

@@ -29,10 +29,10 @@

 #define hidden __attribute__ ((visibility ("hidden")))

-extern int last_cap hidden;

+extern unsigned int last_cap hidden;

 #undef cap_valid

-#define cap_valid(x) ((x) <= (unsigned int)last_cap)

+#define cap_valid(x) ((x) <= last_cap)

 struct transtab {

diff -ru a/src/test/lib_test.c b/src/test/lib_test.c

--- a/src/test/lib_test.c

+++ b/src/test/lib_test.c

@@ -29,7 +29,7 @@

 #include <fcntl.h>

 #include <sys/stat.h>

-int get_last_cap(void)

+static unsigned int get_last_cap(void)

 {

 	int fd;

@@ -41,17 +41,19 @@

 		int num = read(fd, buf, sizeof(buf));

 		if (num > 0) {

 			errno = 0;

-			int val = strtoul(buf, NULL, 10);

+			unsigned int val = strtoul(buf, NULL, 10);

 			if (errno == 0)

 				return val;

 		}

+		close(fd);

 	}

 	return CAP_LAST_CAP;

 }

 int main(void)

 {

-	int rc, i, len, last = get_last_cap();

+	int rc;

+	unsigned int i, len, last = get_last_cap();

 	char *text;

 	void *saved;

@@ -127,7 +129,7 @@

 			abort();

 		}

 		name = capng_capability_to_name(i);

-		if (name == NULL) { 

+		if (name == NULL) {

 			printf("Failed converting capability %d to name\n", i);

 			abort();

 		}