re PR c++/81607 (Conditional operator: "type mismatch in shift expression" error)
authorMarek Polacek <polacek@redhat.com>
Tue, 8 Aug 2017 08:55:43 +0000 (08:55 +0000)
committerMarek Polacek <mpolacek@gcc.gnu.org>
Tue, 8 Aug 2017 08:55:43 +0000 (08:55 +0000)
PR c++/81607
* cp-gimplify.c (cp_fold): If folding exposed a branch of
a COND_EXPR, convert it to the original type of the COND_EXPR, if
they differ.

* g++.dg/other/bitfield6.C: New test.

From-SVN: r250948

gcc/cp/ChangeLog
gcc/cp/cp-gimplify.c
gcc/testsuite/ChangeLog
gcc/testsuite/g++.dg/other/bitfield6.C [new file with mode: 0644]

index 23f6a1d2a7a1d2721fd61e40c6c217d91d0d14d5..93257293d1cc3f98921caaf14167dd03917b71ca 100644 (file)
@@ -1,3 +1,10 @@
+2017-08-08  Marek Polacek  <polacek@redhat.com>
+
+       PR c++/81607
+       * cp-gimplify.c (cp_fold): If folding exposed a branch of
+       a COND_EXPR, convert it to the original type of the COND_EXPR, if
+       they differ.               
+
 2017-08-08  Martin Liska  <mliska@suse.cz>
 
        * call.c: Include header files.
index 528e38816d368ad5da4f28136b3be07bb11bbb58..4a52aa50e77b8193f77c0d6eb3dc46051f9ca1a0 100644 (file)
@@ -2316,9 +2316,9 @@ cp_fold (tree x)
 
       /* A COND_EXPR might have incompatible types in branches if one or both
         arms are bitfields.  If folding exposed such a branch, fix it up.  */
-      if (TREE_CODE (x) != code)
-       if (tree type = is_bitfield_expr_with_lowered_type (x))
-         x = fold_convert (type, x);
+      if (TREE_CODE (x) != code
+         && !useless_type_conversion_p (TREE_TYPE (org_x), TREE_TYPE (x)))
+       x = fold_convert (TREE_TYPE (org_x), x);
 
       break;
 
index c2119f478bab1a293159a2385cc8facdf09c04d9..e08c2e848f404cfe12211b637351c86e5bf47250 100644 (file)
@@ -1,3 +1,8 @@
+2017-08-08  Marek Polacek  <polacek@redhat.com>
+
+       PR c++/81607
+       * g++.dg/other/bitfield6.C: New test.
+
 2017-08-07  Michael Meissner  <meissner@linux.vnet.ibm.com>
 
        PR target/81593
diff --git a/gcc/testsuite/g++.dg/other/bitfield6.C b/gcc/testsuite/g++.dg/other/bitfield6.C
new file mode 100644 (file)
index 0000000..c1e8a17
--- /dev/null
@@ -0,0 +1,9 @@
+// PR c++/81607
+
+int a;
+
+struct b {
+  long c : 32;
+} d;
+
+char f = (903092 ? int(d.c) : 0) << a;