* c-decl.c (warn_missing_noreturn): New global variable.
(c_decode_option): Check for new flags -W{no-}missing-noreturn.
(finish_function): Implement missing noreturn warning.
* c-tree.h (warn_missing_noreturn): Declare extern.
* invoke.texi: Document new flags.
* toplev.c (documented_lang_options): Add description.
From-SVN: r23197
+Tue Oct 20 10:12:17 1998 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
+
+ * c-decl.c (warn_missing_noreturn): New global variable.
+ (c_decode_option): Check for new flags -W{no-}missing-noreturn.
+ (finish_function): Implement missing noreturn warning.
+
+ * c-tree.h (warn_missing_noreturn): Declare extern.
+
+ * invoke.texi: Document new flags.
+
+ * toplev.c (documented_lang_options): Add description.
+
Tue Oct 20 22:16:11 1998 Michael Hayes <m.hayes@elec.canterbury.ac.nz>
* config/c4x/c4x.c (c4x_parallel_process): Disable until BCT
int warn_bad_function_cast;
+/* Warn about functions which might be candidates for attribute noreturn. */
+
+int warn_missing_noreturn;
+
/* Warn about traditional constructs whose meanings changed in ANSI C. */
int warn_traditional;
warn_bad_function_cast = 1;
else if (!strcmp (p, "-Wno-bad-function-cast"))
warn_bad_function_cast = 0;
+ else if (!strcmp (p, "-Wmissing-noreturn"))
+ warn_missing_noreturn = 1;
+ else if (!strcmp (p, "-Wno-missing-noreturn"))
+ warn_missing_noreturn = 0;
else if (!strcmp (p, "-Wpointer-arith"))
warn_pointer_arith = 1;
else if (!strcmp (p, "-Wno-pointer-arith"))
current_function_returns_null |= can_reach_end;
+ if (warn_missing_noreturn
+ && !TREE_THIS_VOLATILE (fndecl)
+ && !current_function_returns_null
+ && !current_function_returns_value)
+ warning ("function might be possible candidate for attribute `noreturn'");
+
if (TREE_THIS_VOLATILE (fndecl) && current_function_returns_null)
warning ("`noreturn' function does return");
else if (warn_return_type && can_reach_end
extern int warn_bad_function_cast;
+/* Warn about functions which might be candidates for attribute noreturn. */
+
+extern int warn_missing_noreturn;
+
/* Warn about traditional constructs whose meanings changed in ANSI C. */
extern int warn_traditional;
-Wimplicit-function-declaration -Wimport
-Werror-implicit-function-declaration -Winline
-Wlarger-than-@var{len} -Wlong-long
--Wmain -Wmissing-declarations
+-Wmain -Wmissing-declarations -Wmissing-noreturn
-Wmissing-prototypes -Wmultichar -Wnested-externs -Wno-import
-Wno-non-template-friend -Wold-style-cast -Woverloaded-virtual
-Wparentheses -Wpointer-arith -Wredundant-decls -Wreorder
Use this option to detect global functions that are not declared in
header files.
+@item -Wmissing-noreturn
+Warn about functions which might be candidates for attribute @code{noreturn}.
+Note these are only possible candidates, not absolute ones. Care should
+be taken to manually verify functions actually do not ever return before
+adding the @code{noreturn} attribute, otherwise subtle code generation
+bugs could be introduced.
+
@item -Wredundant-decls
Warn if anything is declared more than once in the same scope, even in
cases where multiple declaration is valid and changes nothing.
{ "-Wbad-function-cast",
"Warn about casting functions to incompatible types" },
{ "-Wno-bad-function-cast", "" },
+ { "-Wmissing-noreturn",
+ "Warn about functions which might be candidates for attribute noreturn" },
+ { "-Wno-missing-noreturn", "" },
{ "-Wcast-qual", "Warn about casts which discard qualifiers"},
{ "-Wno-cast-qual", "" },
{ "-Wchar-subscripts", "Warn about subscripts whose type is 'char'"},