Fix some front-end memory leaks

src/V3Global.cpp

@@ -35,16 +35,13 @@ void V3Global::boot() {
     m_rootp = new AstNetlist;
 }
 
-void V3Global::clear() {
+void V3Global::shutdown() {
+    VL_DO_CLEAR(delete m_hierPlanp, m_hierPlanp = nullptr);  // delete nullptr is safe
 #ifdef VL_LEAK_CHECKS
     if (m_rootp) VL_DO_CLEAR(m_rootp->deleteTree(), m_rootp = nullptr);
 #endif
 }
 
-void V3Global::shutdown() {
-    VL_DO_CLEAR(delete m_hierPlanp, m_hierPlanp = nullptr);  // delete nullptr is safe
-}
-
 void V3Global::checkTree() const { rootp()->checkTree(); }
 
 void V3Global::readFiles() {

src/V3Global.h

@@ -126,7 +126,6 @@ public:
     // CONSTRUCTORS
     V3Global() {}
     void boot();
-    void clear();
     void shutdown();  // Release allocated resources
     // ACCESSORS (general)
     AstNetlist* rootp() const VL_MT_SAFE { return m_rootp; }

src/V3PreLex.h

@@ -92,6 +92,7 @@ class V3PreProcImp;
 # define yytext V3PreLextext
 # define yyerror V3PreLexerror
 # define yyerrorf V3PreLexerrorf
+# define yylex_destroy V3PreLexlex_destroy
 #endif
 
 #ifndef yyourleng
@@ -117,6 +118,7 @@ extern void yyourtext(const char* textp, size_t size);  // Must call with static
 YY_BUFFER_STATE yy_create_buffer(FILE* file, int size);
 void yy_switch_to_buffer(YY_BUFFER_STATE new_buffer);
 void yy_delete_buffer(YY_BUFFER_STATE b);
+int yylex_destroy();
 
 //======================================================================
 
@@ -190,6 +192,7 @@ public:  // Used only by V3PreLex.cpp and V3PreProc.cpp
             m_streampStack.pop();
         }
         VL_DO_CLEAR(yy_delete_buffer(m_bufferState), m_bufferState = nullptr);
+        yylex_destroy();
     }
 
     // Called by V3PreLex.l from lexer

src/V3PreShell.cpp

@@ -78,6 +78,10 @@ protected:
         }
     }
 
+    void shutdown() {
+        if (s_preprocp) VL_DO_DANGLING(delete s_preprocp, s_preprocp);
+    }
+
     bool preproc(FileLine* fl, const string& modname, VInFilter* filterp, V3ParseImp* parsep,
                  const string& errmsg) {  // "" for no error
         // Preprocess the given module, putting output in vppFilename
@@ -153,6 +157,7 @@ VInFilter* V3PreShellImp::s_filterp = nullptr;
 // V3PreShell
 
 void V3PreShell::boot() { V3PreShellImp::s_preImp.boot(); }
+void V3PreShell::shutdown() { V3PreShellImp::s_preImp.shutdown(); }
 bool V3PreShell::preproc(FileLine* fl, const string& modname, VInFilter* filterp,
                          V3ParseImp* parsep, const string& errmsg) {
     return V3PreShellImp::s_preImp.preproc(fl, modname, filterp, parsep, errmsg);

src/V3PreShell.h

@@ -33,6 +33,7 @@ class V3PreShell final {
     // Static class for calling preprocessor
 public:
     static void boot();
+    static void shutdown();
     static bool preproc(FileLine* fl, const string& modname, VInFilter* filterp,
                         V3ParseImp* parsep, const string& errmsg);
     static void preprocInclude(FileLine* fl, const string& modname);

src/Verilator.cpp

@@ -672,9 +672,6 @@ static void verilate(const string& argString) {
 
     // Final writing shouldn't throw warnings, but...
     V3Error::abortIfWarnings();
-    // Cleanup memory for valgrind leak analysis
-    v3Global.clear();
-    FileLine::deleteAllRemaining();
 }
 
 static string buildMakeCmd(const string& makefile, const string& target) {
@@ -763,7 +760,9 @@ int main(int argc, char** argv) {
     }
 
     // Explicitly release resources
+    V3PreShell::shutdown();
     v3Global.shutdown();
+    FileLine::deleteAllRemaining();
 
     UINFO(1, "Done, Exiting...\n");
 }