diff --git a/regressions/ck_hp/validate/ck_hp_fifo_donner.c b/regressions/ck_hp/validate/ck_hp_fifo_donner.c
index 0866729..759a004 100644
--- a/regressions/ck_hp/validate/ck_hp_fifo_donner.c
+++ b/regressions/ck_hp/validate/ck_hp_fifo_donner.c
@@ -93,7 +93,8 @@ queue_50_50(void *elements)
 
 	/* start barrier */
 	ck_pr_inc_uint(&start_barrier);
-	while (ck_pr_load_uint(&start_barrier) < thread_count + 1);
+	while (ck_pr_load_uint(&start_barrier) < thread_count + 1)
+		ck_pr_stall();
 
 	/* 50/50 enqueue-dequeue */
 	for(j = 0; j < element_count; j++) {
@@ -137,7 +138,8 @@ queue_50_50(void *elements)
 
 	/* end barrier */
 	ck_pr_inc_uint(&end_barrier);
-	while (ck_pr_load_uint(&end_barrier) < thread_count + 1);
+	while (ck_pr_load_uint(&end_barrier) < thread_count + 1)
+		ck_pr_stall();
 
        	return NULL;
 }
diff --git a/regressions/ck_hp/validate/ck_hp_stack.c b/regressions/ck_hp/validate/ck_hp_stack.c
index e728e31..158ea5a 100644
--- a/regressions/ck_hp/validate/ck_hp_stack.c
+++ b/regressions/ck_hp/validate/ck_hp_stack.c
@@ -95,7 +95,8 @@ thread(void *unused CK_CC_UNUSED)
 	}
 
 	ck_pr_inc_uint(&barrier);
-	while (ck_pr_load_uint(&barrier) < n_threads);
+	while (ck_pr_load_uint(&barrier) < n_threads)
+		ck_pr_stall();
 
 	for (i = 0; i < PAIRS; i++) {
 		ck_hp_stack_push_mpmc(&stack, &entry[i]->stack_entry);
@@ -105,7 +106,8 @@ thread(void *unused CK_CC_UNUSED)
 	}
 
 	ck_pr_inc_uint(&e_barrier);
-	while (ck_pr_load_uint(&e_barrier) < n_threads);
+	while (ck_pr_load_uint(&e_barrier) < n_threads)
+		ck_pr_stall();
 
         fprintf(stderr, "Peak: %u (%2.2f%%)\nReclamations: %" PRIu64 "\n\n",
                 record.n_peak,
diff --git a/regressions/ck_pr/validate/Makefile b/regressions/ck_pr/validate/Makefile
index e4706d0..c255b03 100644
--- a/regressions/ck_pr/validate/Makefile
+++ b/regressions/ck_pr/validate/Makefile
@@ -81,3 +81,4 @@ clean:
 	rm -rf *~ *.o $(OBJECTS) *.dSYM
 
 include ../../../build/regressions.build
+CFLAGS+=-D_GNU_SOURCE
diff --git a/regressions/ck_pr/validate/ck_pr_store.c b/regressions/ck_pr/validate/ck_pr_store.c
index de886d7..077851b 100644
--- a/regressions/ck_pr/validate/ck_pr_store.c
+++ b/regressions/ck_pr/validate/ck_pr_store.c
@@ -24,6 +24,9 @@
  * SUCH DAMAGE.
  */
 
+#include "../../common.h"
+#include <ck_pr.h>
+
 #include <inttypes.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -31,9 +34,6 @@
 #include <stdlib.h>
 #include <unistd.h>
 
-#include <ck_pr.h>
-#include "../../common.h"
-
 #ifndef R_REPEAT
 #define R_REPEAT 200000
 #endif
diff --git a/regressions/common.h b/regressions/common.h
index acc484f..b756a41 100644
--- a/regressions/common.h
+++ b/regressions/common.h
@@ -27,6 +27,7 @@
 #include <ck_cc.h>
 #include <ck_pr.h>
 #include <stdarg.h>
+#include <stdio.h>
 #include <stdlib.h>
 
 #ifdef __linux__