Proper memory freeing behavior, courtesy of Travis

src/asm_writing/rewriter.cpp

@@ -650,18 +650,11 @@ void Rewriter::abort() {
     assert(!finished);
     finished = true;
 
-    // This feels hacky: are we really guaranteed to find all of the things we need to delete?
-    std::unordered_set<RewriterVar*> found;
-
-    for (const auto& p : vars_by_location) {
-        found.insert(p.second);
+    for (auto v : args) {
+        v->decUse();
     }
-    for (const auto v : live_outs) {
-        found.insert(v);
-    }
-
-    for (auto v : found) {
-        delete v;
+    for (auto v : live_outs) {
+        v->decUse();
     }
 }
 

src/asm_writing/rewriter.h

@@ -144,12 +144,12 @@ public:
 
     static RewriterVarUsage empty();
 
-#ifndef NDEBUG
     ~RewriterVarUsage() {
-        if (!std::uncaught_exception())
-            assert(done_using);
+        if (!done_using) {
+            assert(std::uncaught_exception());
+            setDoneUsing();
+        }
     }
-#endif
 
     void setDoneUsing();
     bool isDoneUsing();
@@ -278,6 +278,8 @@ public:
             this->abort();
         assert(finished);
 
+        // This check isn't thread safe and should be fine to remove if it causes
+        // issues (along with the nvars/start_vars accounting)
         ASSERT(RewriterVar::nvars == start_vars, "%d %d", RewriterVar::nvars, start_vars);
     }