+2001-11-18 Joseph S. Myers <jsm28@cam.ac.uk>
+
+ * c-common.c (struct disabled_builtin, disabled_builtins,
+ disable_builtin_function, builtin_function_disabled_p): New.
+ (builtin_function_2): Check for disabled built-in functions.
+ * c-common.h (disable_builtin_function): Declare.
+ * c-decl.c (c_decode_option): Handle -fno-builtin-FUNCTION.
+ * doc/invoke.texi: Document -fno-builtin-FUNCTION.
+ * doc/extend.texi: Mention -fno-builtin-FUNCTION.
+
2001-11-17 Craig Rodrigues <rodrigc@gcc.gnu.org>
PR target/4606
}
+/* Linked list of disabled built-in functions. */
+
+typedef struct disabled_builtin
+{
+ const char *name;
+ struct disabled_builtin *next;
+} disabled_builtin;
+static disabled_builtin *disabled_builtins = NULL;
+
+static bool builtin_function_disabled_p PARAMS ((const char *));
+
+/* Disable a built-in function specified by -fno-builtin-NAME. If NAME
+ begins with "__builtin_", give an error. */
+
+void
+disable_builtin_function (name)
+ const char *name;
+{
+ if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
+ error ("cannot disable built-in function `%s'", name);
+ else
+ {
+ disabled_builtin *new = xmalloc (sizeof (disabled_builtin));
+ new->name = name;
+ new->next = disabled_builtins;
+ disabled_builtins = new;
+ }
+}
+
+
+/* Return true if the built-in function NAME has been disabled, false
+ otherwise. */
+
+static bool
+builtin_function_disabled_p (name)
+ const char *name;
+{
+ disabled_builtin *p;
+ for (p = disabled_builtins; p != NULL; p = p->next)
+ {
+ if (strcmp (name, p->name) == 0)
+ return true;
+ }
+ return false;
+}
+
+
/* Possibly define a builtin function with one or two names. BUILTIN_NAME
is an __builtin_-prefixed name; NAME is the ordinary name; one or both
of these may be NULL (though both being NULL is useless).
TREE_SIDE_EFFECTS (bdecl) = 1;
}
}
- if (name != 0 && !flag_no_builtin && !(nonansi_p && flag_no_nonansi_builtin))
+ if (name != 0 && !flag_no_builtin && !builtin_function_disabled_p (name)
+ && !(nonansi_p && flag_no_nonansi_builtin))
{
decl = builtin_function (name, type, function_code, class, NULL);
if (nonansi_p)
frontends. */
extern void c_common_nodes_and_builtins PARAMS ((void));
+extern void disable_builtin_function PARAMS ((const char *));
+
extern tree build_va_arg PARAMS ((tree, tree));
extern const char *c_common_lang_init PARAMS ((const char *));
flag_no_builtin = 0;
else if (!strcmp (p, "-fno-builtin"))
flag_no_builtin = 1;
+ else if (!strncmp (p, "-fno-builtin-", strlen ("-fno-builtin-")))
+ disable_builtin_function (p + strlen ("-fno-builtin-"));
else if (p[0] == '-' && p[1] == 'f' && dump_switch_p (p + 2))
;
else if (!strcmp (p, "-ansi"))
@code{strlen}, @code{strncat}, @code{strncmp}, @code{strncpy},
@code{strpbrk}, @code{strrchr}, @code{strspn}, and @code{strstr} are all
recognized as built-in functions unless @option{-fno-builtin} is
-specified. All of these functions have corresponding versions prefixed
+specified (or @option{-fno-builtin-@var{function}} is specified for an
+individual function). All of these functions have
+corresponding versions prefixed
with @code{__builtin_}, except that the version for @code{sqrt} is
called @code{__builtin_fsqrt}.
@xref{C Dialect Options,,Options Controlling C Dialect}.
@gccoptlist{
-ansi -std=@var{standard} -aux-info @var{filename} @gol
--fno-asm -fno-builtin @gol
+-fno-asm -fno-builtin -fno-builtin-@var{function} @gol
-fhosted -ffreestanding @gol
-trigraphs -traditional -traditional-cpp @gol
-fallow-single-precision -fcond-mismatch @gol
@code{inline} is a standard keyword in ISO C99.
@item -fno-builtin
+@itemx -fno-builtin-@var{function} @r{(C and Objective-C only)}
@opindex fno-builtin
@cindex built-in functions
Don't recognize built-in functions that do not begin with
built-in functions to implement many functions (like
@code{std::strchr}), so that you automatically get efficient code.
+With the @option{-fno-builtin-@var{function}} option, not available
+when compiling C++, only the built-in function @var{function} is
+disabled. @var{function} must not begin with @samp{__builtin_}. If a
+function is named this is not built-in in this version of GCC, this
+option is ignored. There is no corresponding
+@option{-fbuiltin-@var{function}} option; if you wish to enable
+built-in functions selectively when using @option{-fno-builtin} or
+@option{-ffreestanding}, you may define macros such as:
+
+@smallexample
+#define abs(n) __builtin_abs ((n))
+#define strcpy(d, s) __builtin_strcpy ((d), (s))
+@end smallexample
+
@item -fhosted
@opindex fhosted
@cindex hosted environment
+2001-11-18 Joseph S. Myers <jsm28@cam.ac.uk>
+
+ * gcc.dg/no-builtin-1.c: New test.
+
2001-11-16 Jakub Jelinek <jakub@redhat.com>
* gcc.c-torture/execute/20011115-1.c: New test.
--- /dev/null
+/* Test for -fno-builtin-FUNCTION. */
+/* Origin: Joseph Myers <jsm28@cam.ac.uk>. */
+/* { dg-do run } */
+/* { dg-options "-fno-builtin-abs" } */
+
+/* GCC normally handles abs and labs as built-in functions even without
+ optimization. So test that with -fno-builtin-abs, labs is so handled
+ but abs isn't. */
+
+int abs_called = 0;
+
+extern int abs (int);
+extern long labs (long);
+extern void abort (void);
+extern void exit (int);
+
+int
+main (void)
+{
+ if (labs (0) != 0)
+ abort ();
+ if (abs (0) != 0)
+ abort ();
+ if (!abs_called)
+ abort ();
+ exit (0);
+}
+
+/* The labs call above should have been optimized, but the abs call
+ shouldn't have been. */
+
+static int
+abs (int x)
+{ /* { dg-warning "static" "static decl warning" } */
+ abs_called = 1;
+ return (x < 0 ? -1 : x);
+}
+
+static long
+labs (long x)
+{
+ abort ();
+}
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