diff --git a/tests/Makefile b/tests/Makefile
index b0aae93e..3f2637e6 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -68,7 +68,7 @@ all:
 	awk '  printit { print } /END_COVERAGE/ { printit=1}' $< > $<.end.c
 	$(CC) $(CPPFLAGS) -E -DNDEBUG -DWITHIN_COVERAGE $< |grep -v '^#' |awk ' /END_COVERAGE/ { printit=0} printit { print } /START_COVERAGE/ { printit=1 }' |perl -p -e "s/;(?![\"'])/;\n/g ; s/}(?![\"'])/}\n/g ; s/{(?![\"'])/{\n/g" > $<.middle.c
 	cat $<.first.c $<.middle.c $<.end.c > $<.c
-	$(CC) $(CPPFLAGS) -ftest-coverage -fprofile-arcs -O -g $<.c -o $<.exe $(LDFLAGS)
+	$(CC) $(CPPFLAGS) -DBUILD_COVERAGE -ftest-coverage -fprofile-arcs -O -g $<.c -o $<.exe $(LDFLAGS)
 	$(LOG_COMPILER) ./$<.exe
 	LANG=C gcov -b $<.gcno >  `basename $< .c`.synt
 	cat `basename $< .c`.synt
diff --git a/tests/coverage.h b/tests/coverage.h
index 1bb4690b..9ef57a47 100644
--- a/tests/coverage.h
+++ b/tests/coverage.h
@@ -40,10 +40,9 @@
    It'll contain the macro expanded & annotated.
 */
    
-#ifdef WITHIN_COVERAGE
+#if defined(WITHIN_COVERAGE) || defined (BUILD_COVERAGE)
 /* For coverage build, expand the typical macros assert, avoid expanding then
    to not disturb coverage measurement */
-#undef assert
 #undef  M_ASSERT
 #define M_ASSERT(...) (void)0
 #undef  M_ASSERT_SLOW
@@ -127,7 +126,11 @@
 /* Overwrite M_UNLIKELY_NOMEM so that it can never fails, to avoid spurious coverage */
 #undef M_UNLIKELY_NOMEM
 #define M_UNLIKELY_NOMEM(...) 0
+#endif
+
+#ifdef WITHIN_COVERAGE
 /* For coverage build, do not expand other likes NULL, etc. */
+#undef assert
 #undef M_STATIC_FAILURE
 #undef NULL
 #undef M_LIKELY
diff --git a/tests/test-mbitset.c b/tests/test-mbitset.c
index 9c9908a3..8973a594 100644
--- a/tests/test-mbitset.c
+++ b/tests/test-mbitset.c
@@ -21,8 +21,9 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 #include <stdio.h>
-
 #include "m-string.h"
+#include "coverage.h"
+
 #include "m-bitset.h"
 
 static void test1(void)
diff --git a/tests/test-mgenint.c b/tests/test-mgenint.c
index dca895f6..10390ddb 100644
--- a/tests/test-mgenint.c
+++ b/tests/test-mgenint.c
@@ -23,6 +23,8 @@
 #include <stdio.h>
 #include "m-thread.h"
 #include "m-atomic.h"
+#include "m-core.h"
+#include "coverage.h"
 
 #include "m-genint.h"
 
diff --git a/tests/test-mserial-bin.c b/tests/test-mserial-bin.c
index 7199aaa7..4cc54820 100644
--- a/tests/test-mserial-bin.c
+++ b/tests/test-mserial-bin.c
@@ -20,12 +20,14 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
-#include "m-serial-bin.h"
 #include "m-tuple.h"
 #include "m-array.h"
 #include "m-variant.h"
 #include "m-list.h"
 #include "m-dict.h"
+#include "coverage.h"
+
+#include "m-serial-bin.h"
 
 // Serial bin is not supported for standard types if not C11
 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L  
diff --git a/tests/test-mserial-json.c b/tests/test-mserial-json.c
index b376709c..e25f2f4d 100644
--- a/tests/test-mserial-json.c
+++ b/tests/test-mserial-json.c
@@ -20,12 +20,14 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
-#include "m-serial-json.h"
 #include "m-tuple.h"
 #include "m-array.h"
 #include "m-variant.h"
 #include "m-list.h"
 #include "m-dict.h"
+#include "coverage.h"
+
+#include "m-serial-json.h"
 
 // Serial json is not supported for standard types if not C11
 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L  
diff --git a/tests/test-mstring.c b/tests/test-mstring.c
index ca6cd567..2d335d13 100644
--- a/tests/test-mstring.c
+++ b/tests/test-mstring.c
@@ -22,6 +22,9 @@
 */
 
 #define M_USE_ADDITIONAL_CHECKS 1
+#include "m-core.h"
+#include "coverage.h"
+
 #include "m-string.h"
 
 BOUNDED_STRING_DEF(string16, 16)
diff --git a/tests/test-mworker.c b/tests/test-mworker.c
index 30339deb..46d6fab4 100644
--- a/tests/test-mworker.c
+++ b/tests/test-mworker.c
@@ -20,8 +20,9 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
-#include <stdio.h>
-#include <assert.h>
+#include "m-core.h"
+#include "coverage.h"
+
 #include "m-worker.h"
 
 /* Compute Fibonacci number using thread systems. */