fix Issue 12619 - Invalid warning for unused return value of debug me…

…mcpy
dlang · Apr 30, 2014 · 384e23a · 384e23a
1 parent 1672505
commit 384e23a
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Showing 2 changed files with 36 additions and 13 deletions.
diff --git a/src/sideeffect.c b/src/sideeffect.c
@@ -90,12 +90,12 @@ bool lambdaHasSideEffect(Expression *e)
             if (ce->e1->type)
             {
                 Type *t = ce->e1->type->toBasetype();
-                if ((t->ty == Tfunction && ((TypeFunction *)t)->purity > PUREweak &&
-                                           ((TypeFunction *)t)->isnothrow)
-                    ||
-                    (t->ty == Tdelegate && ((TypeFunction *)((TypeDelegate *)t)->next)->purity > PUREweak &&
-                                           ((TypeFunction *)((TypeDelegate *)t)->next)->isnothrow)
-                   )
+                if (t->ty == Tdelegate)
+                    t = ((TypeDelegate *)t)->next;
+                if (t->ty == Tfunction)
+                    ((TypeFunction *)t)->purityLevel();
+                if (t->ty == Tfunction && ((TypeFunction *)t)->purity > PUREweak &&
+                                          ((TypeFunction *)t)->isnothrow)
                 {
                 }
                 else
@@ -152,6 +152,7 @@ void discardValue(Expression *e)
             /* Issue 3882: */
             if (global.params.warnings && !global.gag)
             {
+                CallExp *ce = (CallExp *)e;
                 if (e->type->ty == Tvoid)
                 {
                     /* Don't complain about calling void-returning functions with no side-effect,
@@ -162,12 +163,20 @@ void discardValue(Expression *e)
                      * never call assert (and or not called from inside unittest blocks)
                      */
                 }
-                else
+                else if (ce->e1->type)
                 {
-                    CallExp *ce = (CallExp *)e;
-                    e->warning("Call to function %s without side effects discards return value of type %s, prepend a cast(void) if intentional",
-                               ce->f->toPrettyChars(),
-                               e->type->toChars());
+                    Type *t = ce->e1->type->toBasetype();
+                    if (t->ty == Tdelegate)
+                        t = ((TypeDelegate *)t)->next;
+                    if (t->ty == Tfunction)
+                        ((TypeFunction *)t)->purityLevel();
+                    if (t->ty == Tfunction && ((TypeFunction *)t)->purity > PUREweak &&
+                                              ((TypeFunction *)t)->isnothrow)
+                    {
+                        e->warning("Call to function %s without side effects discards return value of type %s, prepend a cast(void) if intentional",
+                                   ce->f->toPrettyChars(),
+                                   e->type->toChars());
+                    }
                 }
             }
             return;

diff --git a/test/fail_compilation/fail3882.d b/test/fail_compilation/fail3882.d
@@ -1,8 +1,9 @@
 // REQUIRED_ARGS: -w
+// PERMUTE_ARGS: -debug
 /*
 TEST_OUTPUT:
 ---
-fail_compilation/fail3882.d(26): Warning: Call to function fail3882.strictlyPure!int.strictlyPure without side effects discards return value of type int, prepend a cast(void) if intentional
+fail_compilation/fail3882.d(28): Warning: Call to function fail3882.strictlyPure!int.strictlyPure without side effects discards return value of type int, prepend a cast(void) if intentional
 ---
 */
 
@@ -19,9 +20,22 @@ fail_compilation/fail3882.d(26): Warning: Call to function fail3882.strictlyPure
     return x*x;
 }
 
-void main(string args[]) {
+void main()
+{
     int x = 3;
     strictVoidReturn(x);
     nonstrictVoidReturn(x);
     strictlyPure(x);
 }
+
+/******************************************/
+// 12619
+
+extern (C) @system nothrow pure void* memcpy(void* s1, in void* s2, size_t n);
+// -> weakly pure
+
+void test12619() pure
+{
+    ubyte[10] a, b;
+    debug memcpy(a.ptr, b.ptr, 5);  // memcpy call should have side effect
+}