diff --git a/include/verilated_profiler.h b/include/verilated_profiler.h
index 1d8a2c5d4..188e3604d 100644
--- a/include/verilated_profiler.h
+++ b/include/verilated_profiler.h
@@ -290,7 +290,7 @@ void VlPgoProfiler<N_Entries>::write(const char* modelp, const std::string& file
     VL_DEBUG_IF(VL_DBG_MSGF("+prof+vlt+file writing to '%s'\n", filename.c_str()););
 
     if (m_currentHierBlockCost) {
-        fprintf(fp, "profile_data -hier-dpi \"%s\" -cost 64'd%lu\n", modelp,
+        fprintf(fp, "profile_data -hier-dpi \"%s\" -cost 64'd%" PRIu64 "\n", modelp,
                 m_currentHierBlockCost);
     }
 
diff --git a/test_regress/driver.py b/test_regress/driver.py
index d43f4830c..b6f440fea 100755
--- a/test_regress/driver.py
+++ b/test_regress/driver.py
@@ -2863,6 +2863,10 @@ def run_them() -> None:
 if __name__ == '__main__':
     os.environ['PYTHONUNBUFFERED'] = "1"
 
+    # GDB is broken on macOS
+    if platform.system() == "Darwin":
+        os.environ['VERILATOR_TEST_NO_GDB'] = "1"
+
     if ('VERILATOR_ROOT' not in os.environ) and os.path.isfile('../bin/verilator'):
         os.environ['VERILATOR_ROOT'] = os.getcwd() + "/.."
     if 'MAKE' not in os.environ:
diff --git a/test_regress/t/t_flag_ldflags.py b/test_regress/t/t_flag_ldflags.py
index 661f2b1af..276038a94 100755
--- a/test_regress/t/t_flag_ldflags.py
+++ b/test_regress/t/t_flag_ldflags.py
@@ -38,21 +38,11 @@ test.compile(
         "t_flag_ldflags_a.a", "t_flag_ldflags_so.so"
     ])
 
-# On OS X, LD_LIBRARY_PATH is ignored, so set rpath of the exe to find the .so
 if sys.platform == "darwin":
-    test.run(cmd=[
-        "cd " + test.obj_dir + " && install_name_tool -add_rpath @executable_path/.",
-        test.vm_prefix
-    ],
-             check_finished=False)
-
-    test.run(cmd=[
-        "cd " + test.obj_dir + " && install_name_tool -change t_flag_ldflags_so.so" +
-        " @rpath/t_flag_ldflags_so.so", test.vm_prefix
-    ],
-             check_finished=False)
-
-test.execute(run_env="LD_LIBRARY_PATH=" + test.obj_dir + ":" +
-             test.getenv_def("LD_LIBRARY_PATH", ""))
+    test.execute(run_env="DYLD_LIBRARY_PATH=" + test.obj_dir + ":" +
+                 test.getenv_def("DYLD_LIBRARY_PATH", ""))
+else:
+    test.execute(run_env="LD_LIBRARY_PATH=" + test.obj_dir + ":" +
+                 test.getenv_def("LD_LIBRARY_PATH", ""))
 
 test.passes()
diff --git a/test_regress/t/t_gantt_numa.py b/test_regress/t/t_gantt_numa.py
index 7828e3e1f..a58c53bda 100755
--- a/test_regress/t/t_gantt_numa.py
+++ b/test_regress/t/t_gantt_numa.py
@@ -10,6 +10,7 @@
 # Test for bin/verilator_gantt,
 
 import vltest_bootstrap
+import sys
 
 test.scenarios('vltmt')
 test.top_filename = "t/t_gantt.v"
@@ -38,9 +39,10 @@ for trial in range(0, trials):
         "/profile_exec.dat", "| tee " + gantt_log
     ])
 
-    test.file_grep(gantt_log, r'CPU info:')
-    test.file_grep(gantt_log, r'NUMA status += (assigned|%Warning: no /proc/cpuinfo)')
-    # False fails occasionally
-    # test.file_grep_not(gantt_log, r'%Warning:')  # e.g. There were fewer CPUs (1) than threads (3).
+    if sys.platform != "darwin":
+        test.file_grep(gantt_log, r'CPU info:')
+        test.file_grep(gantt_log, r'NUMA status += (assigned|%Warning: no /proc/cpuinfo)')
+        # False fails occasionally
+        # test.file_grep_not(gantt_log, r'%Warning:')  # e.g. There were fewer CPUs (1) than threads (3).
 
 test.passes()
diff --git a/test_regress/t/t_vpi_multidim.cpp b/test_regress/t/t_vpi_multidim.cpp
index 79fbb3bf3..016054d6c 100644
--- a/test_regress/t/t_vpi_multidim.cpp
+++ b/test_regress/t/t_vpi_multidim.cpp
@@ -259,13 +259,13 @@ void _arr_access_format_check(TestVpiHandle& reg_h, int wordSize, const int* low
             strVal_s[spanSize] = '\0';
             value_in.value.str = strVal_s;
         } else if (format == vpiDecStrVal) {
-            sprintf(strVal_s, "%" PRIu64, intVal);
+            snprintf(strVal_s, MAX_SPANSIZE + 1, "%" PRIu64, intVal);
             value_in.value.str = strVal_s;
         } else if (format == vpiHexStrVal) {
-            sprintf(strVal_s, "%0*" PRIx64, (spanSize + 3) / 4, intVal);
+            snprintf(strVal_s, MAX_SPANSIZE + 1, "%0*" PRIx64, (spanSize + 3) / 4, intVal);
             value_in.value.str = strVal_s;
         } else if (format == vpiOctStrVal) {
-            sprintf(strVal_s, "%0*" PRIo64, (spanSize + 2) / 3, intVal);
+            snprintf(strVal_s, MAX_SPANSIZE + 1, "%0*" PRIo64, (spanSize + 2) / 3, intVal);
             value_in.value.str = strVal_s;
         } else if (format == vpiStringVal) {
             const int byteCount = (spanSize + 7) / 8;