/* Handle #pragma, system V.4 style. Supports #pragma weak and #pragma pack.
- Copyright (C) 1992, 1997, 1998, 1999, 2000, 2001, 2002
+ Copyright (C) 1992, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
#include "rtl.h"
#include "tree.h"
#include "function.h"
#include "flags.h"
#include "toplev.h"
#include "ggc.h"
-#include "c-lex.h"
#include "c-common.h"
#include "output.h"
#include "tm_p.h"
+#include "target.h"
#define GCC_BAD(msgid) do { warning (msgid); return; } while (0)
#define GCC_BAD2(msgid, arg) do { warning (msgid, arg); return; } while (0)
-#ifdef HANDLE_PRAGMA_PACK
-static void handle_pragma_pack PARAMS ((cpp_reader *));
-
-#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
-typedef struct align_stack
+typedef struct align_stack GTY(())
{
int alignment;
unsigned int num_pushes;
struct align_stack * prev;
} align_stack;
-static struct align_stack * alignment_stack = NULL;
+static GTY(()) struct align_stack * alignment_stack;
+
+#ifdef HANDLE_PRAGMA_PACK
+static void handle_pragma_pack (cpp_reader *);
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
/* If we have a "global" #pragma pack(<n>) in effect when the first
#pragma pack(push,<n>) is encountered, this stores the value of
maximum_field_alignment in effect. When the final pop_alignment()
#define SET_GLOBAL_ALIGNMENT(ALIGN) \
(default_alignment = maximum_field_alignment = (ALIGN))
-static void push_alignment PARAMS ((int, tree));
-static void pop_alignment PARAMS ((tree));
-static void mark_align_stack PARAMS ((void *));
+static void push_alignment (int, tree);
+static void pop_alignment (tree);
/* Push an alignment value onto the stack. */
static void
-push_alignment (alignment, id)
- int alignment;
- tree id;
+push_alignment (int alignment, tree id)
{
if (alignment_stack == NULL
|| alignment_stack->alignment != alignment
{
align_stack * entry;
- entry = (align_stack *) xmalloc (sizeof (* entry));
+ entry = ggc_alloc (sizeof (* entry));
entry->alignment = alignment;
entry->num_pushes = 1;
/* Undo a push of an alignment onto the stack. */
static void
-pop_alignment (id)
- tree id;
+pop_alignment (tree id)
{
align_stack * entry;
else
maximum_field_alignment = entry->alignment;
- free (alignment_stack);
-
alignment_stack = entry;
}
}
-
-static void
-mark_align_stack (p)
- void *p;
-{
- align_stack *a = *(align_stack **) p;
-
- while (a)
- {
- ggc_mark_tree (a->id);
- a = a->prev;
- }
-}
#else /* not HANDLE_PRAGMA_PACK_PUSH_POP */
#define SET_GLOBAL_ALIGNMENT(ALIGN) (maximum_field_alignment = (ALIGN))
#define push_alignment(ID, N) \
#pragma pack (pop)
#pragma pack (pop, ID) */
static void
-handle_pragma_pack (dummy)
- cpp_reader *dummy ATTRIBUTE_UNUSED;
+handle_pragma_pack (cpp_reader *dummy ATTRIBUTE_UNUSED)
{
tree x, id = 0;
int align = -1;
}
#endif /* HANDLE_PRAGMA_PACK */
-#ifdef HANDLE_PRAGMA_WEAK
-static void apply_pragma_weak PARAMS ((tree, tree));
-static void handle_pragma_weak PARAMS ((cpp_reader *));
+static GTY(()) tree pending_weaks;
-static tree pending_weaks;
+#ifdef HANDLE_PRAGMA_WEAK
+static void apply_pragma_weak (tree, tree);
+static void handle_pragma_weak (cpp_reader *);
static void
-apply_pragma_weak (decl, value)
- tree decl, value;
+apply_pragma_weak (tree decl, tree value)
{
if (value)
- decl_attributes (&decl, build_tree_list (get_identifier ("alias"),
- build_tree_list (NULL, value)),
- 0);
+ {
+ value = build_string (IDENTIFIER_LENGTH (value),
+ IDENTIFIER_POINTER (value));
+ decl_attributes (&decl, build_tree_list (get_identifier ("alias"),
+ build_tree_list (NULL, value)),
+ 0);
+ }
+
+ if (SUPPORTS_WEAK && DECL_EXTERNAL (decl) && TREE_USED (decl)
+ && !DECL_WEAK (decl) /* Don't complain about a redundant #pragma. */
+ && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
+ warning ("%Japplying #pragma weak '%D' after first use results "
+ "in unspecified behavior", decl, decl);
+
declare_weak (decl);
}
void
-maybe_apply_pragma_weak (decl)
- tree decl;
+maybe_apply_pragma_weak (tree decl)
{
tree *p, t, id;
- /* Copied from the check in set_decl_assembler_name. */
- if (TREE_CODE (decl) == FUNCTION_DECL
- || (TREE_CODE (decl) == VAR_DECL
- && (TREE_STATIC (decl)
- || DECL_EXTERNAL (decl)
- || TREE_PUBLIC (decl))))
- id = DECL_ASSEMBLER_NAME (decl);
- else
+ /* Avoid asking for DECL_ASSEMBLER_NAME when it's not needed. */
+
+ /* No weak symbols pending, take the short-cut. */
+ if (!pending_weaks)
+ return;
+ /* If it's not visible outside this file, it doesn't matter whether
+ it's weak. */
+ if (!DECL_EXTERNAL (decl) && !TREE_PUBLIC (decl))
+ return;
+ /* If it's not a function or a variable, it can't be weak.
+ FIXME: what kinds of things are visible outside this file but
+ aren't functions or variables? Should this be an abort() instead? */
+ if (TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
return;
+ id = DECL_ASSEMBLER_NAME (decl);
+
for (p = &pending_weaks; (t = *p) ; p = &TREE_CHAIN (t))
if (id == TREE_PURPOSE (t))
{
/* #pragma weak name [= value] */
static void
-handle_pragma_weak (dummy)
- cpp_reader *dummy ATTRIBUTE_UNUSED;
+handle_pragma_weak (cpp_reader *dummy ATTRIBUTE_UNUSED)
{
tree name, value, x, decl;
enum cpp_ttype t;
decl = identifier_global_value (name);
if (decl && TREE_CODE_CLASS (TREE_CODE (decl)) == 'd')
- apply_pragma_weak (decl, value);
+ {
+ apply_pragma_weak (decl, value);
+ if (value)
+ assemble_alias (decl, value);
+ }
else
pending_weaks = tree_cons (name, value, pending_weaks);
}
#else
void
-maybe_apply_pragma_weak (decl)
- tree decl ATTRIBUTE_UNUSED;
+maybe_apply_pragma_weak (tree decl ATTRIBUTE_UNUSED)
{
}
#endif /* HANDLE_PRAGMA_WEAK */
+/* GCC supports two #pragma directives for renaming the external
+ symbol associated with a declaration (DECL_ASSEMBLER_NAME), for
+ compatibility with the Solaris and Tru64 system headers. GCC also
+ has its own notation for this, __asm__("name") annotations.
+
+ Corner cases of these features and their interaction:
+
+ 1) Both pragmas silently apply only to declarations with external
+ linkage (that is, TREE_PUBLIC || DECL_EXTERNAL). Asm labels
+ do not have this restriction.
+
+ 2) In C++, both #pragmas silently apply only to extern "C" declarations.
+ Asm labels do not have this restriction.
+
+ 3) If any of the three ways of changing DECL_ASSEMBLER_NAME is
+ applied to a decl whose DECL_ASSEMBLER_NAME is already set, and the
+ new name is different, a warning issues and the name does not change.
+
+ 4) The "source name" for #pragma redefine_extname is the DECL_NAME,
+ *not* the DECL_ASSEMBLER_NAME.
+
+ 5) If #pragma extern_prefix is in effect and a declaration occurs
+ with an __asm__ name, the #pragma extern_prefix is silently
+ ignored for that declaration.
+
+ 6) If #pragma extern_prefix and #pragma redefine_extname apply to
+ the same declaration, whichever triggered first wins, and a warning
+ is issued. (We would like to have #pragma redefine_extname always
+ win, but it can appear either before or after the declaration, and
+ if it appears afterward, we have no way of knowing whether a modified
+ DECL_ASSEMBLER_NAME is due to #pragma extern_prefix.) */
+
+static GTY(()) tree pending_redefine_extname;
+
+static void handle_pragma_redefine_extname (cpp_reader *);
+
+/* #pragma redefine_extname oldname newname */
+static void
+handle_pragma_redefine_extname (cpp_reader *dummy ATTRIBUTE_UNUSED)
+{
+ tree oldname, newname, decl, x;
+ enum cpp_ttype t;
+
+ if (c_lex (&oldname) != CPP_NAME)
+ GCC_BAD ("malformed #pragma redefine_extname, ignored");
+ if (c_lex (&newname) != CPP_NAME)
+ GCC_BAD ("malformed #pragma redefine_extname, ignored");
+ t = c_lex (&x);
+ if (t != CPP_EOF)
+ warning ("junk at end of #pragma redefine_extname");
+
+ if (!flag_mudflap && !targetm.handle_pragma_redefine_extname)
+ {
+ if (warn_unknown_pragmas > in_system_header)
+ warning ("#pragma redefine_extname not supported on this target");
+ return;
+ }
+
+ decl = identifier_global_value (oldname);
+ if (decl
+ && (TREE_PUBLIC (decl) || DECL_EXTERNAL (decl))
+ && (TREE_CODE (decl) == FUNCTION_DECL
+ || TREE_CODE (decl) == VAR_DECL)
+ && has_c_linkage (decl))
+ {
+ if (DECL_ASSEMBLER_NAME_SET_P (decl))
+ {
+ const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
+ name = targetm.strip_name_encoding (name);
+
+ if (strcmp (name, IDENTIFIER_POINTER (newname)))
+ warning ("#pragma redefine_extname ignored due to conflict with "
+ "previous rename");
+ }
+ else
+ change_decl_assembler_name (decl, newname);
+ }
+ else
+ /* We have to add this to the rename list even if there's already
+ a global value that doesn't meet the above criteria, because in
+ C++ "struct foo {...};" puts "foo" in the current namespace but
+ does *not* conflict with a subsequent declaration of a function
+ or variable foo. See g++.dg/other/pragma-re-2.C. */
+ add_to_renaming_pragma_list (oldname, newname);
+}
+
+/* This is called from here and from ia64.c. */
void
-init_pragma ()
+add_to_renaming_pragma_list (tree oldname, tree newname)
+{
+ tree previous = purpose_member (oldname, pending_redefine_extname);
+ if (previous)
+ {
+ if (TREE_VALUE (previous) != newname)
+ warning ("#pragma redefine_extname ignored due to conflict with "
+ "previous #pragma redefine_extname");
+ return;
+ }
+
+ pending_redefine_extname
+ = tree_cons (oldname, newname, pending_redefine_extname);
+}
+
+static GTY(()) tree pragma_extern_prefix;
+
+/* #pragma extern_prefix "prefix" */
+static void
+handle_pragma_extern_prefix (cpp_reader *dummy ATTRIBUTE_UNUSED)
+{
+ tree prefix, x;
+ enum cpp_ttype t;
+
+ if (c_lex (&prefix) != CPP_STRING)
+ GCC_BAD ("malformed #pragma extern_prefix, ignored");
+ t = c_lex (&x);
+ if (t != CPP_EOF)
+ warning ("junk at end of #pragma extern_prefix");
+
+ if (targetm.handle_pragma_extern_prefix)
+ /* Note that the length includes the null terminator. */
+ pragma_extern_prefix = (TREE_STRING_LENGTH (prefix) > 1 ? prefix : NULL);
+ else if (warn_unknown_pragmas > in_system_header)
+ warning ("#pragma extern_prefix not supported on this target");
+}
+
+/* Hook from the front ends to apply the results of one of the preceding
+ pragmas that rename variables. */
+
+tree
+maybe_apply_renaming_pragma (tree decl, tree asmname)
+{
+ tree *p, t;
+
+ /* The renaming pragmas are only applied to declarations with
+ external linkage. */
+ if ((TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
+ || (!TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl))
+ || !has_c_linkage (decl))
+ return asmname;
+
+ /* If the DECL_ASSEMBLER_NAME is already set, it does not change,
+ but we may warn about a rename that conflicts. */
+ if (DECL_ASSEMBLER_NAME_SET_P (decl))
+ {
+ const char *oldname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
+ oldname = targetm.strip_name_encoding (oldname);
+
+ if (asmname && strcmp (TREE_STRING_POINTER (asmname), oldname))
+ warning ("asm declaration ignored due to "
+ "conflict with previous rename");
+
+ /* Take any pending redefine_extname off the list. */
+ for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
+ if (DECL_NAME (decl) == TREE_PURPOSE (t))
+ {
+ /* Only warn if there is a conflict. */
+ if (strcmp (IDENTIFIER_POINTER (TREE_VALUE (t)), oldname))
+ warning ("#pragma redefine_extname ignored due to "
+ "conflict with previous rename");
+
+ *p = TREE_CHAIN (t);
+ break;
+ }
+ return 0;
+ }
+
+ /* Find out if we have a pending #pragma redefine_extname. */
+ for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
+ if (DECL_NAME (decl) == TREE_PURPOSE (t))
+ {
+ tree newname = TREE_VALUE (t);
+ *p = TREE_CHAIN (t);
+
+ /* If we already have an asmname, #pragma redefine_extname is
+ ignored (with a warning if it conflicts). */
+ if (asmname)
+ {
+ if (strcmp (TREE_STRING_POINTER (asmname),
+ IDENTIFIER_POINTER (newname)) != 0)
+ warning ("#pragma redefine_extname ignored due to "
+ "conflict with __asm__ declaration");
+ return asmname;
+ }
+
+ /* Otherwise we use what we've got; #pragma extern_prefix is
+ silently ignored. */
+ return build_string (IDENTIFIER_LENGTH (newname),
+ IDENTIFIER_POINTER (newname));
+ }
+
+ /* If we've got an asmname, #pragma extern_prefix is silently ignored. */
+ if (asmname)
+ return asmname;
+
+ /* If #pragma extern_prefix is in effect, apply it. */
+ if (pragma_extern_prefix)
+ {
+ const char *prefix = TREE_STRING_POINTER (pragma_extern_prefix);
+ size_t plen = TREE_STRING_LENGTH (pragma_extern_prefix) - 1;
+
+ const char *id = IDENTIFIER_POINTER (DECL_NAME (decl));
+ size_t ilen = IDENTIFIER_LENGTH (DECL_NAME (decl));
+
+ char *newname = alloca (plen + ilen + 1);
+
+ memcpy (newname, prefix, plen);
+ memcpy (newname + plen, id, ilen + 1);
+
+ return build_string (plen + ilen, newname);
+ }
+
+ /* Nada. */
+ return 0;
+}
+
+/* Front-end wrapper for pragma registration to avoid dragging
+ cpplib.h in almost everywhere. */
+void
+c_register_pragma (const char *space, const char *name,
+ void (*handler) (struct cpp_reader *))
+{
+ cpp_register_pragma (parse_in, space, name, handler);
+}
+
+/* Set up front-end pragmas. */
+void
+init_pragma (void)
{
#ifdef HANDLE_PRAGMA_PACK
- cpp_register_pragma (parse_in, 0, "pack", handle_pragma_pack);
+ c_register_pragma (0, "pack", handle_pragma_pack);
#endif
#ifdef HANDLE_PRAGMA_WEAK
- cpp_register_pragma (parse_in, 0, "weak", handle_pragma_weak);
- ggc_add_tree_root (&pending_weaks, 1);
-#endif
-#ifdef REGISTER_TARGET_PRAGMAS
- REGISTER_TARGET_PRAGMAS (parse_in);
+ c_register_pragma (0, "weak", handle_pragma_weak);
#endif
-#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
- ggc_add_root (&alignment_stack, 1, sizeof(alignment_stack),
- mark_align_stack);
+ c_register_pragma (0, "redefine_extname", handle_pragma_redefine_extname);
+ c_register_pragma (0, "extern_prefix", handle_pragma_extern_prefix);
+
+ c_register_pragma ("GCC", "pch_preprocess", c_common_pch_pragma);
+
+#ifdef REGISTER_TARGET_PRAGMAS
+ REGISTER_TARGET_PRAGMAS ();
#endif
}
+
+#include "gt-c-pragma.h"