diff --git a/.github/workflows/build-and-test.yaml b/.github/workflows/build-and-test.yaml
index a7ca264..ab623f2 100644
--- a/.github/workflows/build-and-test.yaml
+++ b/.github/workflows/build-and-test.yaml
@@ -10,7 +10,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-20.04, ubuntu-22.04 ]
+        os: [ubuntu-20.04, ubuntu-22.04]
 
     name: ${{ matrix.os }}
 
diff --git a/src/gotcha_auxv.c b/src/gotcha_auxv.c
index abffc58..9fe0984 100644
--- a/src/gotcha_auxv.c
+++ b/src/gotcha_auxv.c
@@ -90,7 +90,7 @@ struct link_map *get_vdso_from_auxv() {
 
   ElfW(Phdr) *vdso_phdrs = NULL;
   ElfW(Half) vdso_phdr_num, p;
-  ElfW(Addr) vdso_dynamic;
+  ElfW(Addr) vdso_dynamic = 0;
 
   parse_auxv_contents();
   if (vdso_ehdr) {
diff --git a/test/hammer/CMakeLists.txt b/test/hammer/CMakeLists.txt
index 748bd6e..e64ba9f 100644
--- a/test/hammer/CMakeLists.txt
+++ b/test/hammer/CMakeLists.txt
@@ -14,7 +14,7 @@ set(XSIZE 1)
 set(YSIZE 1)
 
 set(CMAKE_BUILD_TYPE Debug)
-SET(CMAKE_CXX_FLAGS_DEBUG " ${CMAKE_CXX_FLAGS_DEBUG} -O0 -Wall -Werror -Wextra")
+SET(CMAKE_CXX_FLAGS_DEBUG " ${CMAKE_CXX_FLAGS_DEBUG} -Wall -Werror -Wextra")
 
 add_definitions(-DXSIZE=${XSIZE})
 add_definitions(-DYSIZE=${YSIZE})
diff --git a/test/symver/retX_new.c b/test/symver/retX_new.c
index a16a09f..b72bb2d 100644
--- a/test/symver/retX_new.c
+++ b/test/symver/retX_new.c
@@ -12,9 +12,8 @@ for more details.  You should have received a copy of the GNU Lesser General
 Public License along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
-
+#include "sym_macro.h"
+// clang-format off
+SYMVER_ATTRIBUTE(retX_new, retX@@GOTCHA_2)
 int retX_new(int x) { return x; }
-__asm__(
-    "\t.globl  __retX_new\n"
-    "\t.equiv  __retX_new,retX_new\n"
-    "\t.symver __retX_new,retX@@GOTCHA_2");
+// clang-format on
\ No newline at end of file
diff --git a/test/symver/retX_old.c b/test/symver/retX_old.c
index ebf9a3b..39612a3 100644
--- a/test/symver/retX_old.c
+++ b/test/symver/retX_old.c
@@ -12,9 +12,9 @@ for more details.  You should have received a copy of the GNU Lesser General
 Public License along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
+#include "sym_macro.h"
 
+// clang-format off
+SYMVER_ATTRIBUTE(retX_old, retX@GOTCHA_1)
 int retX_old(int x) { return -x; }
-__asm__(
-    "\t.globl  __retX_old\n"
-    "\t.equiv  __retX_old,retX_old\n"
-    "\t.symver __retX_old,retX@GOTCHA_1");
+// clang-format on
diff --git a/test/symver/sym_macro.h b/test/symver/sym_macro.h
new file mode 100644
index 0000000..80b5d0e
--- /dev/null
+++ b/test/symver/sym_macro.h
@@ -0,0 +1,16 @@
+#ifndef GOTCHA_SYM_MACRO_H
+#define GOTCHA_SYM_MACRO_H
+#ifdef __has_attribute
+#if __has_attribute(__symver__)
+#define SYMVER_ATTRIBUTE(sym, symver) __attribute__((__symver__(#symver)))
+#endif
+#endif
+#ifndef SYMVER_ATTRIBUTE
+#define SYMVER_ATTRIBUTE(sym, symver)  \
+  __asm__("\t.globl  __" #sym          \
+          "\n"                         \
+          "\t.equiv  __" #sym "," #sym \
+          "\n"                         \
+          "\t.symver __" #sym "," #symver);
+#endif
+#endif  // GOTCHA_SYM_MACRO_H