Internals: Always attempt to release resources on termination (#6416)

Replace std::exit with v3Global.exit, and make V3Error::vlAbort call
v3Global.shutdown. This gives us an opportunity to release resources to
facilitate leak checking even when exiting early on an error.

Note we still don't release most resources by default without
VL_LEAK_CHECKS, so there is no behaviour change there.

src/V3Error.cpp

@@ -97,19 +97,19 @@ void V3ErrorGuarded::vlAbortOrExit() VL_REQUIRES(m_mutex) {
         std::cerr << msgPrefix() << "Aborting since under --debug" << endl;
         V3Error::vlAbort();
     }
-#ifndef V3ERROR_NO_GLOBAL_
-    else if (v3Global.opt.verilateJobs() > 1
-             && v3Global.mainThreadId() != std::this_thread::get_id()) {
-        VL_GCOV_DUMP();  // No static destructors are called, thus must be called manually.
 
-        // Exit without triggering any global destructors.
-        // Used to prevent detached V3ThreadPool jobs accessing destroyed static objects.
+#ifndef V3ERROR_NO_GLOBAL_
+    if (v3Global.opt.verilateJobs() > 1 && v3Global.mainThreadId() != std::this_thread::get_id()) {
+        // No static destructors are called, thus must be called manually.
+        VL_GCOV_DUMP();
+        // Exit without triggering any global destructors. Used to prevent
+        // detached V3ThreadPool jobs accessing destroyed static objects.
         ::_exit(1);
     }
+    v3Global.vlExit(1);
+#else
+    std::exit(1);
 #endif
-    else {
-        std::exit(1);
-    }
 }
 
 string V3ErrorGuarded::warnMoreSpaces() VL_REQUIRES(m_mutex) {
@@ -369,6 +369,9 @@ void V3Error::abortIfWarnings() {
 
 void V3Error::vlAbort() {
     VL_GCOV_DUMP();
+#ifndef V3ERROR_NO_GLOBAL_
+    v3Global.shutdown();
+#endif
     std::abort();
 }
 std::ostringstream& V3Error::v3errorPrep(V3ErrorCode code) VL_ACQUIRE(s().m_mutex) {