Now handles forward declared structures correctly.

Issue #166

interpreter.h

@@ -515,6 +515,7 @@ void TypeParseIdentPart(struct ParseState *Parser, struct ValueType *BasicTyp, s
 void TypeParse(struct ParseState *Parser, struct ValueType **Typ, char **Identifier, int *IsStatic);
 struct ValueType *TypeGetMatching(Picoc *pc, struct ParseState *Parser, struct ValueType *ParentType, enum BaseType Base, int ArraySize, const char *Identifier, int AllowDuplicates);
 struct ValueType *TypeCreateOpaqueStruct(Picoc *pc, struct ParseState *Parser, const char *StructName, int Size);
+int TypeIsForwardDeclared(struct ParseState *Parser, struct ValueType *Typ);
 
 /* heap.c */
 void HeapInit(Picoc *pc, int StackSize);

tests/56_cross_structure.c

@@ -0,0 +1,18 @@
+#include <stdio.h>
+
+struct s1;
+
+struct s2
+{
+ struct s1 *s;
+};
+
+struct s1
+{
+ struct s2 *s;
+};
+
+void main()
+{
+ printf("ok\n");
+}

tests/56_cross_structure.expect

@@ -0,0 +1 @@
+ok

tests/Makefile

@@ -49,7 +49,8 @@ TESTS= 00_assignment.test \
  51_static.test \
  52_unnamed_enum.test \
  54_goto.test \
- 55_array_initialiser.test
+ 55_array_initialiser.test \
+ 56_cross_structure.test
 
 %.test: %.expect %.c
  @echo Test: $*...

type.c

@@ -198,15 +198,18 @@ void TypeParseStruct(struct ParseState *Parser, struct ValueType **Typ, int IsSt
  StructIdentifier = PlatformMakeTempName(pc, TempNameBuf);
  }
 
- *Typ = TypeGetMatching(pc, Parser, &Parser->pc->UberType, IsStruct ? TypeStruct : TypeUnion, 0, StructIdentifier, Token != TokenLeftBrace);
+ *Typ = TypeGetMatching(pc, Parser, &Parser->pc->UberType, IsStruct ? TypeStruct : TypeUnion, 0, StructIdentifier, TRUE);
+ if (Token == TokenLeftBrace && (*Typ)->Members != NULL)
+ ProgramFail(Parser, "data type '%t' is already defined", *Typ);
 
  Token = LexGetToken(Parser, NULL, FALSE);
  if (Token != TokenLeftBrace)
  { 
  /* use the already defined structure */
+#if 0
  if ((*Typ)->Members == NULL)
  ProgramFail(Parser, "structure '%s' isn't defined", LexValue->Val->Identifier);
-
+#endif 
  return;
  }
 
@@ -527,3 +530,14 @@ void TypeParse(struct ParseState *Parser, struct ValueType **Typ, char **Identif
  TypeParseIdentPart(Parser, BasicType, Typ, Identifier);
 }
 
+/* check if a type has been fully defined - otherwise it's just a forward declaration */
+int TypeIsForwardDeclared(struct ParseState *Parser, struct ValueType *Typ)
+{
+ if (Typ->Base == TypeArray)
+ return TypeIsForwardDeclared(Parser, Typ->FromType);
+
+ if ( (Typ->Base == TypeStruct || Typ->Base == TypeUnion) && Typ->Members == NULL)
+ return TRUE;
+
+ return FALSE;
+}

variable.c

@@ -185,6 +185,10 @@ struct Value *VariableDefineButIgnoreIdentical(struct ParseState *Parser, char *
  int DeclLine;
  int DeclColumn;
 
+ /* is the type a forward declaration? */
+ if (TypeIsForwardDeclared(Parser, Typ))
+ ProgramFail(Parser, "type '%t' isn't defined", Typ);
+
  if (IsStatic)
  {
  char MangledName[LINEBUFFER_MAX];