diff --git a/test/asm/atomic_cmpset.c b/test/asm/atomic_cmpset.c
index 6161b8f12d..abf57b15b3 100644
--- a/test/asm/atomic_cmpset.c
+++ b/test/asm/atomic_cmpset.c
@@ -42,26 +42,26 @@ int nreps = 100;
 int nthreads = 2;
 int enable_verbose = 0;
 
-volatile int32_t vol32;
-int32_t val32;
-int32_t old32;
-int32_t new32;
+volatile int32_t vol32 = 0;
+int32_t val32 = 0;
+int32_t old32 = 0;
+int32_t new32 = 0;
 
 #if OPAL_HAVE_ATOMIC_MATH_64
-volatile int64_t vol64;
-int64_t val64;
-int64_t old64;
-int64_t new64;
+volatile int64_t vol64 = 0;
+int64_t val64 = 0;
+int64_t old64 = 0;
+int64_t new64 = 0;
 #endif
 
-volatile int volint;
-int valint;
-int oldint;
-int newint;
+volatile int volint = 0;
+int valint = 0;
+int oldint = 0;
+int newint = 0;
 
-volatile void *volptr;
-void *oldptr;
-void *newptr;
+volatile void *volptr = NULL;
+void *oldptr = NULL;
+void *newptr = NULL;
 
 
 static void *thread_main(void *arg)
diff --git a/test/datatype/ddt_raw.c b/test/datatype/ddt_raw.c
index a0c3023a9c..e42e40d6d2 100644
--- a/test/datatype/ddt_raw.c
+++ b/test/datatype/ddt_raw.c
@@ -39,7 +39,7 @@ mpicc -DHAVE_CONFIG_H -I. -I../../include -I../../../ompi-trunk/include  -I../..
 #define DUMP_DATA_AFTER_COMMIT 0x00000001
 #define CHECK_PACK_UNPACK      0x00000002
 
-uint32_t remote_arch;
+uint32_t remote_arch = 0xffffffff;
 
 static int test_upper( unsigned int length )
 {
diff --git a/test/datatype/ddt_test.c b/test/datatype/ddt_test.c
index 9b17487a6a..5f520ae504 100644
--- a/test/datatype/ddt_test.c
+++ b/test/datatype/ddt_test.c
@@ -41,7 +41,7 @@ mpicc -DHAVE_CONFIG_H -I. -I../../include -I../../../ompi-trunk/include  -I../..
 #define DUMP_DATA_AFTER_COMMIT 0x00000001
 #define CHECK_PACK_UNPACK      0x00000002
 
-uint32_t remote_arch;
+uint32_t remote_arch = 0xffffffff;
 
 static int test_upper( unsigned int length )
 {
diff --git a/test/datatype/opal_datatype_test.c b/test/datatype/opal_datatype_test.c
index b948e90c86..891ddfb53f 100644
--- a/test/datatype/opal_datatype_test.c
+++ b/test/datatype/opal_datatype_test.c
@@ -41,7 +41,7 @@ gcc -DHAVE_CONFIG_H -I. -I../../include -I../.. -I../../include -I../../../ompi-
 #define GET_TIME(TV)   gettimeofday( &(TV), NULL )
 #define ELAPSED_TIME(TSTART, TEND)  (((TEND).tv_sec - (TSTART).tv_sec) * 1000000 + ((TEND).tv_usec - (TSTART).tv_usec))
 
-uint32_t remote_arch;
+uint32_t remote_arch = 0xffffffff;
 
 /**
  * Generic function computing the amount of memory to be allocated to fit
diff --git a/test/datatype/unpack_ooo.c b/test/datatype/unpack_ooo.c
index 64410c3b4f..6c2919039c 100644
--- a/test/datatype/unpack_ooo.c
+++ b/test/datatype/unpack_ooo.c
@@ -26,17 +26,17 @@
 
 #define N 331
 
-uint32_t remote_arch;
+uint32_t remote_arch = 0xffffffff;
 
 struct foo_t {
     int i[3];
     double d[3];
-} foo, *bar;
+} foo = {}, *bar = NULL;
 
 struct pfoo_t {
     int i[2];
     double d[2];
-} pfoo, *pbar;
+} pfoo = {}, *pbar = NULL;
 
 static void print_hex(void* ptr, int count, int space)
 {