re PR c/64918 (invalid (?) warning when initializing structure)

	PR c/64918
	* c.opt (Woverride-init-side-effects): New option.

	* c-typeck.c (add_pending_init): Use OPT_Woverride_init_side_effects.
	(output_init_element): Likewise.

	* doc/invoke.texi: Document -Woverride-init-side-effects.

	* gcc.dg/Woverride-init-side-effects-1.c: New test.
	* gcc.dg/Woverride-init-side-effects-2.c: New test.

From-SVN: r222894

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f1c685a..d38918d 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-05-08  Marek Polacek  <polacek@redhat.com>
+
+       PR c/64918
+       * doc/invoke.texi: Document -Woverride-init-side-effects.
+
 2015-05-07  Marek Polacek  <polacek@redhat.com>
 
        PR c/65179

diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 6f14121..57f83c9 100644 (file)
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,8 @@
+2015-05-08  Marek Polacek  <polacek@redhat.com>
+
+       PR c/64918
+       * c.opt (Woverride-init-side-effects): New option.
+
 2015-05-07  Marek Polacek  <polacek@redhat.com>
 
        PR c/65179

diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 48947b4..3774a89 100644 (file)
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -709,6 +709,10 @@ Woverride-init
 C ObjC Var(warn_override_init) Warning EnabledBy(Wextra)
 Warn about overriding initializers without side effects
 
+Woverride-init-side-effects
+C ObjC Var(warn_override_init_side_effects) Init(1) Warning
+Warn about overriding initializers with side effects
+
 Wpacked-bitfield-compat
 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
 Warn about packed bit-fields whose offset changed in GCC 4.4

diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index ccd1e72..3b8f491 100644 (file)
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,9 @@
+2015-05-08  Marek Polacek  <polacek@redhat.com>
+
+       PR c/64918
+       * c-typeck.c (add_pending_init): Use OPT_Woverride_init_side_effects.
+       (output_init_element): Likewise.
+
 2015-05-07  Marek Polacek  <polacek@redhat.com>
 
        PR c/65179

diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c
index 73275aa..3fcb7c2 100644 (file)
--- a/gcc/c/c-typeck.c
+++ b/gcc/c/c-typeck.c
@@ -7968,7 +7968,7 @@ add_pending_init (location_t loc, tree purpose, tree value, tree origtype,
              if (!implicit)
                {
                  if (TREE_SIDE_EFFECTS (p->value))
-                   warning_init (loc, 0,
+                   warning_init (loc, OPT_Woverride_init_side_effects,
                                  "initialized field with side-effects "
                                  "overwritten");
                  else if (warn_override_init)
@@ -7998,7 +7998,7 @@ add_pending_init (location_t loc, tree purpose, tree value, tree origtype,
              if (!implicit)
                {
                  if (TREE_SIDE_EFFECTS (p->value))
-                   warning_init (loc, 0,
+                   warning_init (loc, OPT_Woverride_init_side_effects,
                                  "initialized field with side-effects "
                                  "overwritten");
                  else if (warn_override_init)
@@ -8530,7 +8530,7 @@ output_init_element (location_t loc, tree value, tree origtype,
       if (!implicit)
        {
          if (TREE_SIDE_EFFECTS (constructor_elements->last ().value))
-           warning_init (loc, 0,
+           warning_init (loc, OPT_Woverride_init_side_effects,
                          "initialized field with side-effects overwritten");
          else if (warn_override_init)
            warning_init (loc, OPT_Woverride_init,

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 934edd6..cb5ae17 100644 (file)
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -266,6 +266,7 @@ Objective-C and Objective-C++ Dialects}.
 -Wmissing-field-initializers -Wmissing-include-dirs @gol
 -Wno-multichar  -Wnonnull  -Wnormalized=@r{[}none@r{|}id@r{|}nfc@r{|}nfkc@r{]} @gol
 -Wodr  -Wno-overflow  -Wopenmp-simd @gol
+-Woverride-init-side-effects @gol
 -Woverlength-strings  -Wpacked  -Wpacked-bitfield-compat  -Wpadded @gol
 -Wparentheses  -Wpedantic-ms-format -Wno-pedantic-ms-format @gol
 -Wpointer-arith  -Wno-pointer-to-int-cast @gol
@@ -5197,6 +5198,13 @@ This warning is included in @option{-Wextra}.  To get other
 @option{-Wextra} warnings without this one, use @option{-Wextra
 -Wno-override-init}.
 
+@item -Woverride-init-side-effects @r{(C and Objective-C only)}
+@opindex Woverride-init-side-effects
+@opindex Wno-override-init-side-effects
+Warn if an initialized field with side effects is overridden when
+using designated initializers (@pxref{Designated Inits, , Designated
+Initializers}).  This warning is enabled by default.
+
 @item -Wpacked
 @opindex Wpacked
 @opindex Wno-packed

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4ffc428..79b2aa2 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2015-05-08  Marek Polacek  <polacek@redhat.com>
+
+       PR c/64918
+       * gcc.dg/Woverride-init-side-effects-1.c: New test.
+       * gcc.dg/Woverride-init-side-effects-2.c: New test.
+
 2015-05-07  Marek Polacek  <polacek@redhat.com>
 
        PR c/65179

diff --git a/gcc/testsuite/gcc.dg/Woverride-init-side-effects-1.c b/gcc/testsuite/gcc.dg/Woverride-init-side-effects-1.c
new file mode 100644 (file)
index 0000000..50f198d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Woverride-init-side-effects-1.c
@@ -0,0 +1,25 @@
+/* PR c/64918 */
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+struct S { int m, n; };
+union U { short s; long int l; };
+
+void
+foo (int i)
+{
+  int a[] = {
+    [0] = ++i,
+    [1] = i,
+    [0] = 42   /* { dg-warning "initialized field with side-effects overwritten" } */
+  };
+  struct S s = {
+    .n = ++i,
+    .m = i,
+    .n = i     /* { dg-warning "initialized field with side-effects overwritten" } */
+  };
+  union U u = {
+    .s = i--,
+    .l = 42    /* { dg-warning "initialized field with side-effects overwritten" } */
+  };
+}

diff --git a/gcc/testsuite/gcc.dg/Woverride-init-side-effects-2.c b/gcc/testsuite/gcc.dg/Woverride-init-side-effects-2.c
new file mode 100644 (file)
index 0000000..5927189
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Woverride-init-side-effects-2.c
@@ -0,0 +1,25 @@
+/* PR c/64918 */
+/* { dg-do compile } */
+/* { dg-options "-Wno-override-init-side-effects" } */
+
+struct S { int m, n; };
+union U { short s; long int l; };
+
+void
+foo (int i)
+{
+  int a[] = {
+    [0] = ++i,
+    [1] = i,
+    [0] = 42
+  };
+  struct S s = {
+    .n = ++i,
+    .m = i,
+    .n = i
+  };
+  union U u = {
+    .s = i--,
+    .l = 42
+  };
+}