diff --git a/userland/bin/ls/ls.c b/userland/bin/ls/ls.c
index 6dd8c88..2041bc8 100644
--- a/userland/bin/ls/ls.c
+++ b/userland/bin/ls/ls.c
@@ -177,7 +177,7 @@ print(const char *path)
 			typech = '?';
 		}
 
-		printf("%crwx------ %2d root  %-8llu",
+		printf("%crwx------ %2d root  %-7llu ",
 		       typech,
 		       statbuf.st_nlink,
 		       statbuf.st_size);
diff --git a/userland/bin/tac/tac.c b/userland/bin/tac/tac.c
index 3e0a260..edaa48d 100644
--- a/userland/bin/tac/tac.c
+++ b/userland/bin/tac/tac.c
@@ -197,11 +197,9 @@ dumpdata(void)
 
 	indexsize = dolseek(indexfd, indexname, 0, SEEK_CUR);
 	pos = indexsize;
-	while (1) {
+	assert(pos % sizeof(x) == 0);
+	while (pos > 0) {
 		pos -= sizeof(x);
-		if (pos == 0) {
-			break;
-		}
 		assert(pos >= 0);
 		dolseek(indexfd, indexname, pos, SEEK_SET);
 
diff --git a/userland/lib/libtest/Makefile b/userland/lib/libtest/Makefile
index cf0422a..2752d19 100644
--- a/userland/lib/libtest/Makefile
+++ b/userland/lib/libtest/Makefile
@@ -5,7 +5,7 @@
 TOP=../../..
 .include "$(TOP)/mk/os161.config.mk"
 
-SRCS=triple.c quint.c
+SRCS=triple.c
 LIB=test
 
 .include  "$(TOP)/mk/os161.lib.mk"
diff --git a/userland/testbin/Makefile b/userland/testbin/Makefile
index e5cf502..647f229 100644
--- a/userland/testbin/Makefile
+++ b/userland/testbin/Makefile
@@ -7,10 +7,10 @@ TOP=../..
 
 SUBDIRS=add argtest badcall bigexec bigfile bigfork bigseek bloat conman \
 	crash ctest dirconc dirseek dirtest f_test factorial farm faulter \
-	filetest forkbomb forktest frack guzzle hash hog huge kitchen \
+	filetest forkbomb forktest frack hash hog huge \
 	malloctest matmult multiexec palin parallelvm poisondisk psort \
-	quinthuge quintmat quintsort randcall redirect rmdirtest rmtest \
-	sbrktest schedpong sink sort sparsefile sty tail tictac triplehuge \
+	randcall redirect rmdirtest rmtest \
+	sbrktest schedpong sort sparsefile tail tictac triplehuge \
 	triplemat triplesort usemtest zero
 
 # But not:
diff --git a/userland/testbin/badcall/bad_open.c b/userland/testbin/badcall/bad_open.c
index 5ce66cd..3d317ed 100644
--- a/userland/testbin/badcall/bad_open.c
+++ b/userland/testbin/badcall/bad_open.c
@@ -62,7 +62,7 @@ open_empty(void)
 
 	report_begin("open empty string");
 	rv = open("", O_RDONLY);
-	report_check2(rv, errno, 0, EINVAL);
+	report_check(rv, errno, EINVAL);
 	if (rv>=0) {
 		close(rv);
 	}
diff --git a/userland/testbin/badcall/bad_pipe.c b/userland/testbin/badcall/bad_pipe.c
index 350c3d8..172579c 100644
--- a/userland/testbin/badcall/bad_pipe.c
+++ b/userland/testbin/badcall/bad_pipe.c
@@ -68,6 +68,11 @@ pipe_unaligned(void)
 
 	rv = pipe((int *)ptr);
 	report_survival(rv, errno);
+	if (rv == 0) {
+		memmove(fds, ptr, 2*sizeof(int));
+		close(fds[0]);
+		close(fds[1]);
+	}
 }
 
 void
diff --git a/userland/testbin/filetest/filetest.c b/userland/testbin/filetest/filetest.c
index ae93c38..dc062ec 100644
--- a/userland/testbin/filetest/filetest.c
+++ b/userland/testbin/filetest/filetest.c
@@ -46,7 +46,7 @@
 int
 main(int argc, char *argv[])
 {
-	static char writebuf[40] = "Twiddle dee dee, Twiddle dum dum.......\n";
+	static char writebuf[41] = "Twiddle dee dee, Twiddle dum dum.......\n";
 	static char readbuf[41];
 
 	const char *file;
diff --git a/userland/testbin/forktest/forktest.c b/userland/testbin/forktest/forktest.c
index 4f7fed3..46e5da2 100644
--- a/userland/testbin/forktest/forktest.c
+++ b/userland/testbin/forktest/forktest.c
@@ -133,25 +133,52 @@ void
 test(int nowait)
 {
 	int pid0, pid1, pid2, pid3;
+	int depth = 0;
 
 	/*
 	 * Caution: This generates processes geometrically.
 	 *
 	 * It is unrolled to encourage gcc to registerize the pids,
 	 * to prevent wait/exit problems if fork corrupts memory.
+	 *
+	 * Note: if the depth prints trigger and show that the depth
+	 * is too small, the most likely explanation is that the fork
+	 * child is returning from the write() inside putchar()
+	 * instead of from fork() and thus skipping the depth++. This
+	 * is a fairly common problem caused by races in the kernel
+	 * fork code.
 	 */
 
 	pid0 = dofork();
+	depth++;
 	putchar('A');
+	if (depth != 1) {
+		warnx("depth %d, should be 1", depth);
+	}
 	check();
+
 	pid1 = dofork();
+	depth++;
 	putchar('B');
+	if (depth != 2) {
+		warnx("depth %d, should be 2", depth);
+	}
 	check();
+
 	pid2 = dofork();
+	depth++;
 	putchar('C');
+	if (depth != 3) {
+		warnx("depth %d, should be 3", depth);
+	}
 	check();
+
 	pid3 = dofork();
+	depth++;
 	putchar('D');
+	if (depth != 4) {
+		warnx("depth %d, should be 4", depth);
+	}
 	check();
 
 	/*
diff --git a/userland/testbin/hog/hog.c b/userland/testbin/hog/hog.c
index 7b69f15..9c6e2b5 100644
--- a/userland/testbin/hog/hog.c
+++ b/userland/testbin/hog/hog.c
@@ -31,7 +31,7 @@
  * hog.c
  * 	Spawned by several other user programs to test time-slicing.
  *
- * This does not differ from guzzle in any important way.
+ * Loops consuming CPU cycles.
  */
 
 int
diff --git a/userland/testbin/multiexec/multiexec.c b/userland/testbin/multiexec/multiexec.c
index a7d41c9..b6f157d 100644
--- a/userland/testbin/multiexec/multiexec.c
+++ b/userland/testbin/multiexec/multiexec.c
@@ -134,6 +134,7 @@ semP(struct usem *sem, size_t num)
 	if (read(sem->fd, c, num) < 0) {
 		err(1, "%s: read", sem->name);
 	}
+	(void)c;
 }
 
 static
diff --git a/userland/testbin/parallelvm/parallelvm.c b/userland/testbin/parallelvm/parallelvm.c
index a213197..953764a 100644
--- a/userland/testbin/parallelvm/parallelvm.c
+++ b/userland/testbin/parallelvm/parallelvm.c
@@ -283,16 +283,24 @@ static
 void
 semP(struct usem *sem, size_t num)
 {
-	if (read(sem->fd, NULL, num) < 0) {
+	char c[num];
+
+	if (read(sem->fd, c, num) < 0) {
 		err(1, "%s: read", sem->name);
 	}
+	(void)c;
 }
 
 static
 void
 semV(struct usem *sem, size_t num)
 {
-	if (write(sem->fd, NULL, num) < 0) {
+	char c[num];
+
+	/* semfs does not use these values, but be conservative */
+	memset(c, 0, num);
+
+	if (write(sem->fd, c, num) < 0) {
 		err(1, "%s: write", sem->name);
 	}
 }
@@ -336,7 +344,12 @@ makeprocs(bool dowait)
 	for (i=0; i<NJOBS; i++) {
 		pids[i] = fork();
 		if (pids[i]<0) {
-			warn("fork");
+			warn("fork (process %d)", i);
+			if (dowait) {
+				semopen(&s1);
+				semV(&s1, 1);
+				semclose(&s1);
+			}
 		}
 		if (pids[i]==0) {
 			/* child */
diff --git a/userland/testbin/schedpong/usem.c b/userland/testbin/schedpong/usem.c
index 95b7030..b6c54b1 100644
--- a/userland/testbin/schedpong/usem.c
+++ b/userland/testbin/schedpong/usem.c
@@ -35,6 +35,7 @@
 
 #include <stdio.h>
 #include <stdarg.h>
+#include <string.h>
 #include <unistd.h>
 #include <err.h>
 
@@ -84,9 +85,9 @@ void
 Pn(struct usem *sem, unsigned count)
 {
 	ssize_t r;
-	char c;
+	char c[count];
 
-	r = read(sem->fd, &c, count);
+	r = read(sem->fd, c, count);
 	if (r < 0) {
 		err(1, "%s: read", sem->name);
 	}
@@ -105,9 +106,12 @@ void
 Vn(struct usem *sem, unsigned count)
 {
 	ssize_t r;
-	char c;
+	char c[count];
 
-	r = write(sem->fd, &c, count);
+	/* semfs does not use these values, but be conservative */
+	memset(c, 0, count);
+
+	r = write(sem->fd, c, count);
 	if (r < 0) {
 		err(1, "%s: write", sem->name);
 	}