Merge pull request #3648 from yebblies/issue10071

Issue 10071 - 'real' alignment wrong on OS X 32 bit

src/declaration.c

@@ -1853,6 +1853,8 @@ void VarDeclaration::setFieldOffset(AggregateDeclaration *ad, unsigned *poffset,
         ad->sizeok = SIZEOKfwd;             // cannot finish; flag as forward referenced
         return;
     }
+    if (t->ty == Terror)
+        return;
 
 
     unsigned memsize      = (unsigned)t->size(loc);  // size of member

src/struct.c

@@ -431,15 +431,11 @@ void AggregateDeclaration::alignmember(
             break;
 
         case (structalign_t) STRUCTALIGN_DEFAULT:
-        {
-            /* Must match what the corresponding C compiler's default
-             * alignment behavior is.
-             */
-            assert(size != 3);
-            unsigned sa = (size == 0 || 8 < size) ? 8 : size;
-            *poffset = (*poffset + sa - 1) & ~(sa - 1);
+            // Alignment in Target::fieldalignsize must match what the
+            // corresponding C compiler's default alignment behavior is.
+            assert(size > 0 && !(size & (size - 1)));
+            *poffset = (*poffset + size - 1) & ~(size - 1);
             break;
-        }
 
         default:
             // Align on alignment boundary, which must be a positive power of 2

test/runnable/cppa.d

@@ -279,6 +279,20 @@ void test11()
 }
 /****************************************/
 
+struct Struct10071
+{
+    void *p;
+    real r;
+}
+
+extern(C++) size_t offset10071();
+void test10071()
+{
+    assert(offset10071() == Struct10071.r.offsetof);
+}
+
+/****************************************/
+
 char[100] valistbuffer;
 
 extern(C++) void myvprintfx(const(char)* format, va_list va)
@@ -331,6 +345,7 @@ void main()
     test4();
     test5();
     test6();
+    test10071();
     test7();
     test8();
     test11802();

test/runnable/extra-files/cppb.cpp

@@ -182,6 +182,20 @@ extern "C" { int foo7()
 
 /**************************************/
 
+struct Struct10071
+{
+    void *p;
+    long double r;
+};
+
+size_t offset10071()
+{
+    Struct10071 s;
+    return (char *)&s.r - (char *)&s;
+}
+
+/**************************************/
+
 void foo8(const char *p)
 {
 }