r320017 - Ignore pointers to incomplete types when diagnosing misaligned addresses

[Roger Ferrer Ibanez via cfe-commits]

Author: rogfer01
Date: Thu Dec  7 01:23:50 2017
New Revision: 320017

URL: http://llvm.org/viewvc/llvm-project?rev=320017&view=rev
Log:
Ignore pointers to incomplete types when diagnosing misaligned addresses

This is a fix for PR35509 in which we crash because we attempt to compute the
alignment of an incomplete type.

Differential Revision: https://reviews.llvm.org/D40895


Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp
    cfe/trunk/test/SemaCXX/address-packed.cpp

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=320017&r1=320016&r2=320017&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Thu Dec  7 01:23:50 2017
@@ -12399,8 +12399,9 @@ void Sema::DiscardMisalignedMemberAddres
                           MisalignedMember(Op));
       if (MA != MisalignedMembers.end() &&
           (T->isIntegerType() ||
-           (T->isPointerType() &&
-            Context.getTypeAlignInChars(T->getPointeeType()) <= MA->Alignment)))
+           (T->isPointerType() && (T->getPointeeType()->isIncompleteType() ||
+                                   Context.getTypeAlignInChars(
+                                       T->getPointeeType()) <= MA->Alignment))))
         MisalignedMembers.erase(MA);
     }
   }

Modified: cfe/trunk/test/SemaCXX/address-packed.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/address-packed.cpp?rev=320017&r1=320016&r2=320017&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/address-packed.cpp (original)
+++ cfe/trunk/test/SemaCXX/address-packed.cpp Thu Dec  7 01:23:50 2017
@@ -112,3 +112,12 @@ void g1() {
   S<float> s3;
   s3.get(); // expected-note {{in instantiation of member function 'S<float>::get'}}
 }
+
+// PR35509
+typedef long L1;
+struct Incomplete;
+struct S2 {
+  L1 d;
+  Incomplete *e() const;
+} __attribute__((packed));
+Incomplete *S2::e() const { return (Incomplete *)&d; } // no-warning