+2002-10-09 Zack Weinberg <zack@codesourcery.com>
+
+ PR c/7353
+ * c-decl.c (start_decl): Unconditionally issue error for
+ 'typedef foo = bar'.
+ (finish_decl): Remove special case for TYPE_DECL with initializer.
+
+ * doc/extend.texi: Delete "Naming Types" section. Change all
+ cross-references to that section to refer to "Typeof" instead.
+ Add the useful safe-max()-macro example from "Naming Types" to
+ "Typeof", rewritten using that extension. Add some compatibility
+ notes to "Typeof."
+
2002-10-09 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* loop.c: Revert 2002-08-15 change.
switch (TREE_CODE (decl))
{
case TYPE_DECL:
- /* typedef foo = bar means give foo the same type as bar.
- We haven't parsed bar yet, so `finish_decl' will fix that up.
- Any other case of an initialization in a TYPE_DECL is an error. */
- if (pedantic || list_length (declspecs) > 1)
- {
- error ("typedef `%s' is initialized",
- IDENTIFIER_POINTER (DECL_NAME (decl)));
- initialized = 0;
- }
+ error ("typedef `%s' is initialized",
+ IDENTIFIER_POINTER (DECL_NAME (decl)));
+ initialized = 0;
break;
case FUNCTION_DECL:
init = 0;
if (init)
- {
- if (TREE_CODE (decl) != TYPE_DECL)
- store_init_value (decl, init);
- else
- {
- /* typedef foo = bar; store the type of bar as the type of foo. */
- TREE_TYPE (decl) = TREE_TYPE (init);
- DECL_INITIAL (decl) = init = 0;
- }
- }
+ store_init_value (decl, init);
/* Deduce size of array from initialization, if not already known */
if (TREE_CODE (type) == ARRAY_TYPE
+2002-10-09 Zack Weinberg <zack@codesourcery.com>
+
+ * decl.c (start_decl): Unconditionally issue error for
+ 'typedef foo = bar'.
+ (cp_finish_decl): Remove special case for TYPE_DECL with initializer.
+ (grokdeclarator): Remove redundant error for 'typedef foo = bar'.
+
2002-10-09 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* decl2.c (prune_vtable_vardecl): Delete unused function.
2002-10-02 Matt Austern <austern@apple.com>
* decl.c (walk_vtables_r): Fixed typo that caused result to
never get a nonzero value.
-
+
2002-10-02 Roger Sayle <roger@eyesopen.com>
PR optimization/6627
* class.c (check_field_decls): Changed warning about const member
variables so that it doesn't get issued for a class aggregate.
-
+
2002-10-01 Mark Mitchell <mark@codesourcery.com>
* decl.c (cp_finish_decl): Make sure array types are laid out,
(dfs_unuse_fields): Likewise.
* tree.c (pod_type_p): Handle error_mark_node.
(zero_init_p): Likewise.
- * typeck.c (lookup_anon_field): Skip FIELD_DECLs for base
+ * typeck.c (lookup_anon_field): Skip FIELD_DECLs for base
subobjects.
* typeck2.c (store_init_value): Remove #if 0'd code.
(force_store_init_value): Remove.
(process_init_constructor): Use build_zero_init.
-
+
2002-09-29 Nathan Sidwell <nathan@codesourcery.com>
PR c++/7788
even number of bytes when computing the size without virtual
bases.
* cp/cp-tree.h (abi_version_at_least): New macro.
-
+
2002-09-21 Kazu Hirata <kazu@cs.umass.edu>
* ChangeLog: Follow spelling conventions.
switch (TREE_CODE (decl))
{
case TYPE_DECL:
- /* typedef foo = bar means give foo the same type as bar.
- We haven't parsed bar yet, so `cp_finish_decl' will fix that up.
- Any other case of an initialization in a TYPE_DECL is an error. */
- if (pedantic || list_length (declspecs) > 1)
- {
- error ("typedef `%D' is initialized", decl);
- initialized = 0;
- }
+ error ("typedef `%D' is initialized", decl);
+ initialized = 0;
break;
case FUNCTION_DECL:
/* Take care of TYPE_DECLs up front. */
if (TREE_CODE (decl) == TYPE_DECL)
{
- if (init && DECL_INITIAL (decl))
- {
- /* typedef foo = bar; store the type of bar as the type of foo. */
- TREE_TYPE (decl) = type = TREE_TYPE (init);
- DECL_INITIAL (decl) = init = NULL_TREE;
- }
if (type != error_mark_node
&& IS_AGGR_TYPE (type) && DECL_NAME (decl))
{
bad_specifiers (decl, "type", virtualp, quals != NULL_TREE,
inlinep, friendp, raises != NULL_TREE);
- if (initialized)
- error ("typedef declaration includes an initializer");
-
return decl;
}
* Labels as Values:: Getting pointers to labels, and computed gotos.
* Nested Functions:: As in Algol and Pascal, lexical scoping of functions.
* Constructing Calls:: Dispatching a call to another function.
-* Naming Types:: Giving a name to the type of some expression.
* Typeof:: @code{typeof}: referring to the type of an expression.
* Lvalues:: Using @samp{?:}, @samp{,} and casts in lvalues.
* Conditionals:: Omitting the middle operand of a @samp{?:} expression.
the initial value of a static variable.
If you don't know the type of the operand, you can still do this, but you
-must use @code{typeof} (@pxref{Typeof}) or type naming (@pxref{Naming
-Types}).
+must use @code{typeof} (@pxref{Typeof}).
Statement expressions are not supported fully in G++, and their fate
there is unclear. (It is possible that they will become fully supported
returned by @code{__builtin_apply}.
@end deftypefn
-@node Naming Types
-@section Naming an Expression's Type
-@cindex naming types
-
-You can give a name to the type of an expression using a @code{typedef}
-declaration with an initializer. Here is how to define @var{name} as a
-type name for the type of @var{exp}:
-
-@example
-typedef @var{name} = @var{exp};
-@end example
-
-This is useful in conjunction with the statements-within-expressions
-feature. Here is how the two together can be used to define a safe
-``maximum'' macro that operates on any arithmetic type:
-
-@example
-#define max(a,b) \
- (@{typedef _ta = (a), _tb = (b); \
- _ta _a = (a); _tb _b = (b); \
- _a > _b ? _a : _b; @})
-@end example
-
@cindex underscores in variables in macros
@cindex @samp{_} in variables in macros
@cindex local variables in macros
used. For example, you can use it in a declaration, in a cast, or inside
of @code{sizeof} or @code{typeof}.
+@code{typeof} is often useful in conjunction with the
+statements-within-expressions feature. Here is how the two together can
+be used to define a safe ``maximum'' macro that operates on any
+arithmetic type and evaluates each of its arguments exactly once:
+
+@example
+#define max(a,b) \
+ (@{ typeof (a) _a = (a); \
+ typeof (b) _b = (b); \
+ _a > _b ? _a : _b; @})
+@end example
+
+@noindent
+Some more examples of the use of @code{typeof}:
+
@itemize @bullet
@item
This declares @code{y} with the type of what @code{x} points to.
pointers to @code{char}.
@end itemize
+@emph{Compatibility Note:} In addition to @code{typeof}, GCC 2 supported
+a more limited extension which permitted one to write
+
+@example
+typedef @var{T} = @var{expr};
+@end example
+
+@noindent
+with the effect of declaring @var{T} to have the type of the expression
+@var{expr}. This extension does not work with GCC 3 (versions between
+3.0 and 3.2 will crash; 3.2.1 and later give an error). Code which
+relies on it should be rewritten to use @code{typeof}:
+
+@example
+typedef typeof(@var{expr}) @var{T};
+@end example
+
+@noindent
+This will work with all versions of GCC@.
+
@node Lvalues
@section Generalized Lvalues
@cindex compound expressions as lvalues
However, side effects in @code{X} or @code{Y} may cause unintended
behavior. For example, @code{MIN (i++, j++)} will fail, incrementing
-the smaller counter twice. A GNU C extension allows you to write safe
-macros that avoid this kind of problem (@pxref{Naming Types,,Naming an
-Expression's Type}). However, writing @code{MIN} and @code{MAX} as
-macros also forces you to use function-call notation for a
-fundamental arithmetic operation. Using GNU C++ extensions, you can
-write @w{@samp{int min = i <? j;}} instead.
+the smaller counter twice. The GNU C @code{typeof} extension allows you
+to write safe macros that avoid this kind of problem (@pxref{Typeof}).
+However, writing @code{MIN} and @code{MAX} as macros also forces you to
+use function-call notation for a fundamental arithmetic operation.
+Using GNU C++ extensions, you can write @w{@samp{int min = i <? j;}}
+instead.
Since @code{<?} and @code{>?} are built into the compiler, they properly
handle expressions with side-effects; @w{@samp{int min = i++ <? j++;}}
+2002-10-09 Zack Weinberg <zack@codesourcery.com>
+
+ * g++.dg/ext/typedef-init.C: New test.
+ * gcc.dg/typedef-init.c: New test.
+
2002-10-09 Neil Booth <neil@daikokuya.co.uk>
* gcc.dg/cpp/paste13.c: New test.
--- /dev/null
+/* { dg-do compile } */
+/* { dg-options "-fpermissive" } // suppress default -pedantic-errors */
+
+/* This code used to be a legitimate, if dubious, extension. However,
+ it's been broken since GCC 3.0 (caused ICE) and we have now removed
+ the extension. See PR c/7353.
+
+ C++ issues a warning in addition to the error, since this construct
+ appears to be a case of implicit int (forbidden in std. C++) until
+ we get to the equals sign. */
+
+typedef A = 0; /* { dg-error "initialized" "typedef A = B" } */
+ /* { dg-warning "no type" "also warns" { target *-*-* } 12 } */
+A a; /* { dg-bogus "" "no error cascade" } */
--- /dev/null
+/* { dg-do compile } */
+/* { dg-options "-std=gnu89" } // suppress default -pedantic-errors */
+
+/* This code used to be a legitimate, if dubious, extension. However,
+ it's been broken since GCC 3.0 (caused ICE) and we have now removed
+ the extension. See PR c/7353. */
+
+typedef A = 0; /* { dg-error "initialized" "typedef A = B" } */
+A a; /* { dg-bogus "" "no error cascade" } */
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