diff --git a/libunwind/test/forceunwind.pass.cpp b/libunwind/test/forceunwind.pass.cpp
--- a/libunwind/test/forceunwind.pass.cpp
+++ b/libunwind/test/forceunwind.pass.cpp
@@ -15,6 +15,7 @@
 // Basic test for _Unwind_ForcedUnwind.
 // See libcxxabi/test/forced_unwind* tests too.
 
+#undef NDEBUG
 #include <assert.h>
 #include <dlfcn.h>
 #include <signal.h>
diff --git a/libunwind/test/libunwind_02.pass.cpp b/libunwind/test/libunwind_02.pass.cpp
--- a/libunwind/test/libunwind_02.pass.cpp
+++ b/libunwind/test/libunwind_02.pass.cpp
@@ -10,6 +10,7 @@
 // TODO: Figure out why this fails with Memory Sanitizer.
 // XFAIL: msan
 
+#undef NDEBUG
 #include <assert.h>
 #include <stdlib.h>
 #include <unwind.h>
diff --git a/libunwind/test/signal_frame.pass.cpp b/libunwind/test/signal_frame.pass.cpp
--- a/libunwind/test/signal_frame.pass.cpp
+++ b/libunwind/test/signal_frame.pass.cpp
@@ -21,6 +21,7 @@
 // are necessary to run this test.
 // UNSUPPORTED: target=powerpc{{(64)?}}-ibm-aix
 
+#undef NDEBUG
 #include <assert.h>
 #include <stdlib.h>
 #include <libunwind.h>
diff --git a/libunwind/test/signal_unwind.pass.cpp b/libunwind/test/signal_unwind.pass.cpp
--- a/libunwind/test/signal_unwind.pass.cpp
+++ b/libunwind/test/signal_unwind.pass.cpp
@@ -13,6 +13,7 @@
 // TODO: Figure out why this fails with Memory Sanitizer.
 // XFAIL: msan
 
+#undef NDEBUG
 #include <assert.h>
 #include <dlfcn.h>
 #include <signal.h>
diff --git a/libunwind/test/unw_getcontext.pass.cpp b/libunwind/test/unw_getcontext.pass.cpp
--- a/libunwind/test/unw_getcontext.pass.cpp
+++ b/libunwind/test/unw_getcontext.pass.cpp
@@ -7,6 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#undef NDEBUG
 #include <assert.h>
 #include <libunwind.h>
 
diff --git a/libunwind/test/unwind_leaffunction.pass.cpp b/libunwind/test/unwind_leaffunction.pass.cpp
--- a/libunwind/test/unwind_leaffunction.pass.cpp
+++ b/libunwind/test/unwind_leaffunction.pass.cpp
@@ -13,6 +13,7 @@
 // TODO: Figure out why this fails with Memory Sanitizer.
 // XFAIL: msan
 
+#undef NDEBUG
 #include <assert.h>
 #include <dlfcn.h>
 #include <signal.h>