From 157549e119b46989da7c807246dd362ee12ba003 Mon Sep 17 00:00:00 2001
From: David Anderson <dvander@alliedmods.net>
Date: Sun, 30 Nov 2014 18:56:37 -0800
Subject: [PATCH] Fix a bug where aliased constructors of nullable methodmaps
 could not be used.

---
 sourcepawn/compiler/sc.h                           |  3 ++-
 sourcepawn/compiler/sc2.cpp                        |  7 +++++--
 sourcepawn/compiler/sc3.cpp                        | 14 ++++++++++++--
 .../compiler/tests/ok-use-aliased-constructor.sp   | 12 ++++++++++++
 4 files changed, 31 insertions(+), 5 deletions(-)
 create mode 100644 sourcepawn/compiler/tests/ok-use-aliased-constructor.sp

diff --git a/sourcepawn/compiler/sc.h b/sourcepawn/compiler/sc.h
index e98e7cfc..07f3d444 100644
--- a/sourcepawn/compiler/sc.h
+++ b/sourcepawn/compiler/sc.h
@@ -246,6 +246,7 @@ struct methodmap_method_s;
 
 typedef struct value_s {
   symbol *sym;          /* symbol in symbol table, NULL for (constant) expression */
+  symbol *proxy;        /* original symbol if resolved via a proxy */
   cell constval;        /* value of the constant expression (if ident==iCONSTEXPR)
                          * also used for the size of a literal array */
   int tag;              /* tag (of the expression) */
@@ -640,7 +641,7 @@ void delete_symbol(symbol *root,symbol *sym);
 void delete_symbols(symbol *root,int level,int del_labels,int delete_functions);
 int refer_symbol(symbol *entry,symbol *bywhom);
 void markusage(symbol *sym,int usage);
-symbol *findglb(const char *name,int filter);
+symbol *findglb(const char *name,int filter,symbol **alias = NULL);
 symbol *findloc(const char *name);
 symbol *findconst(const char *name,int *matchtag);
 symbol *finddepend(const symbol *parent);
diff --git a/sourcepawn/compiler/sc2.cpp b/sourcepawn/compiler/sc2.cpp
index f4d83b9d..353b0b86 100644
--- a/sourcepawn/compiler/sc2.cpp
+++ b/sourcepawn/compiler/sc2.cpp
@@ -2999,7 +2999,7 @@ void markusage(symbol *sym,int usage)
  *
  *  Returns a pointer to the global symbol (if found) or NULL (if not found)
  */
-symbol *findglb(const char *name,int filter)
+symbol *findglb(const char *name, int filter, symbol **alias)
 {
   /* find a symbol with a matching automaton first */
   symbol *sym=NULL;
@@ -3024,8 +3024,11 @@ symbol *findglb(const char *name,int filter)
   if (sym==NULL)
     sym=FindInHashTable(sp_Globals,name,fcurrent);
 
-  if (sym && sym->ident == iPROXY)
+  if (sym && sym->ident == iPROXY) {
+    if (alias)
+      *alias = sym;
     return sym->target;
+  }
 
   return sym;
 }
diff --git a/sourcepawn/compiler/sc3.cpp b/sourcepawn/compiler/sc3.cpp
index 240739ec..6f3c7977 100644
--- a/sourcepawn/compiler/sc3.cpp
+++ b/sourcepawn/compiler/sc3.cpp
@@ -2265,7 +2265,12 @@ restart:
         error(4,symname);             /* function not defined */
       } /* if */
 
-      if (sym->flags & flgPROXIED) {
+      // Check whether we're calling a constructor. This is a bit hacky, since
+      // we're relying on whatever the lval state is.
+      if ((sym->flags & flgPROXIED) &&
+          lval1->proxy &&
+          lval1->proxy->target == sym)
+      {
         // Only constructors should be proxied, but we check anyway.
         assert(!implicitthis);
         if (methodmap_t *methodmap = methodmap_find_by_tag(sym->tag)) {
@@ -2310,6 +2315,7 @@ restart:
 
     funcenum_t *fe = funcenum_for_symbol(target);
     lval1->sym = NULL;
+    lval1->proxy = NULL;
     lval1->ident = iCONSTEXPR;
     lval1->constval = (public_index << 1) | 1;
     lval1->tag = fe->tag;
@@ -2396,7 +2402,8 @@ static int primary(value *lval)
       } /* if */
     } /* if */
     /* now try a global variable */
-    if ((sym=findglb(st,sSTATEVAR))!=0) {
+    symbol *alias = NULL;
+    if ((sym = findglb(st, sSTATEVAR, &alias)) != 0) {
       if (sym->ident==iFUNCTN || sym->ident==iREFFUNC) {
         /* if the function is only in the table because it was inserted as a
          * stub in the first pass (i.e. it was "used" but never declared or
@@ -2408,6 +2415,7 @@ static int primary(value *lval)
         if ((sym->usage & uDEFINE)==0)
           error(17,st);
         lval->sym=sym;
+        lval->proxy=alias;
         lval->ident=sym->ident;
         lval->tag=sym->tag;
         if (sym->ident==iARRAY || sym->ident==iREFARRAY) {
@@ -2431,6 +2439,7 @@ static int primary(value *lval)
     assert(sym!=NULL);
     assert(sym->ident==iFUNCTN || sym->ident==iREFFUNC);
     lval->sym=sym;
+    lval->proxy=alias;
     lval->ident=sym->ident;
     lval->tag=sym->tag;
     return FALSE;       /* return 0 for function (not an lvalue) */
@@ -2446,6 +2455,7 @@ static int primary(value *lval)
 static void clear_value(value *lval)
 {
   lval->sym=NULL;
+  lval->proxy=NULL;
   lval->constval=0L;
   lval->tag=0;
   lval->ident=0;
diff --git a/sourcepawn/compiler/tests/ok-use-aliased-constructor.sp b/sourcepawn/compiler/tests/ok-use-aliased-constructor.sp
new file mode 100644
index 00000000..1dca0339
--- /dev/null
+++ b/sourcepawn/compiler/tests/ok-use-aliased-constructor.sp
@@ -0,0 +1,12 @@
+native Handle:CreateHandle();
+
+methodmap Handle __nullable__
+{
+	public native Handle() = CreateHandle;
+	public native ~Handle();
+};
+
+public main()
+{
+	CreateHandle();
+}