Re-allow using delegate.ptr and .funcptr as lvalues

dlang · May 27, 2014 · 313243c · 313243c
1 parent 9d48c47
commit 313243c
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Showing 5 changed files with 61 additions and 25 deletions.
diff --git a/src/e2ir.c b/src/e2ir.c
@@ -4326,16 +4326,23 @@ elem *toElem(Expression *e, IRState *irs)
 
         void visit(DelegatePtrExp *dpe)
         {
+            // *cast(void**)(&dg)
             elem *e = dpe->e1->toElem(irs);
-            e = el_una(I64 ? OP128_64 : OP64_32, totym(dpe->type), e);
+            Type *tb1 = dpe->e1->type->toBasetype();
+            e = addressElem(e, tb1);
+            e = el_una(OPind, totym(dpe->type), e);
             el_setLoc(e, dpe->loc);
             result = e;
         }
 
         void visit(DelegateFuncptrExp *dfpe)
         {
+            // *cast(void**)(&dg + size_t.sizeof)
             elem *e = dfpe->e1->toElem(irs);
-            e = el_una(OPmsw, totym(dfpe->type), e);
+            Type *tb1 = dfpe->e1->type->toBasetype();
+            e = addressElem(e, tb1);
+            e = el_bin(OPadd, TYnptr, e, el_long(TYsize_t, I64 ? 8 : 4));
+            e = el_una(OPind, totym(dfpe->type), e);
             el_setLoc(e, dfpe->loc);
             result = e;
         }

diff --git a/src/expression.c b/src/expression.c
@@ -10227,6 +10227,17 @@ Expression *DelegatePtrExp::semantic(Scope *sc)
     return this;
 }
 
+int DelegatePtrExp::isLvalue()
+{
+    return e1->isLvalue();
+}
+
+Expression *DelegatePtrExp::toLvalue(Scope *sc, Expression *e)
+{
+    e1 = e1->toLvalue(sc, e);
+    return this;
+}
+
 /********************** DelegateFuncptrExp **************************************/
 
 DelegateFuncptrExp::DelegateFuncptrExp(Loc loc, Expression *e1)
@@ -10251,6 +10262,17 @@ Expression *DelegateFuncptrExp::semantic(Scope *sc)
     return this;
 }
 
+int DelegateFuncptrExp::isLvalue()
+{
+    return e1->isLvalue();
+}
+
+Expression *DelegateFuncptrExp::toLvalue(Scope *sc, Expression *e)
+{
+    e1 = e1->toLvalue(sc, e);
+    return this;
+}
+
 /*********************** ArrayExp *************************************/
 
 // e1 [ i1, i2, i3, ... ]

diff --git a/src/expression.h b/src/expression.h
@@ -1103,6 +1103,8 @@ class DelegatePtrExp : public UnaExp
 public:
     DelegatePtrExp(Loc loc, Expression *e1);
     Expression *semantic(Scope *sc);
+    int isLvalue();
+    Expression *toLvalue(Scope *sc, Expression *e);
     void accept(Visitor *v) { v->visit(this); }
 };
 
@@ -1111,6 +1113,8 @@ class DelegateFuncptrExp : public UnaExp
 public:
     DelegateFuncptrExp(Loc loc, Expression *e1);
     Expression *semantic(Scope *sc);
+    int isLvalue();
+    Expression *toLvalue(Scope *sc, Expression *e);
     void accept(Visitor *v) { v->visit(this); }
 };
 

diff --git a/test/fail_compilation/faildg.d b/test/fail_compilation/faildg.d
diff --git a/test/runnable/delegate.d b/test/runnable/delegate.d
@@ -309,6 +309,31 @@ void test2472()
 
 /********************************************************/
 
+void testAssign()
+{
+    static class C
+    {
+        int a;
+        this(int a) { this.a = a; }
+        int funca() { return a; }
+        int funcb() { return a + 1; }
+    }
+
+    auto x = new C(5);
+    auto y = new C(7);
+
+    auto dg = &x.funca;
+    assert(dg() == 5);
+    dg.funcptr = &C.funcb;
+    assert(dg() == 6);
+    dg.ptr = cast(void*)y;
+    assert(dg() == 8);
+    dg.funcptr = &C.funca;
+    assert(dg() == 7);
+}
+
+/********************************************************/
+
 int main()
 {
     test1();
@@ -325,6 +350,7 @@ int main()
     test13();
     test2472();
     test8257();
+    testAssign();
 
     printf("Success\n");
     return 0;