2010-04-27 Manuel López-Ibáñez <manu@gcc.gnu.org>

	    Jan Hubicka <hubicka@ucw.cz>

	* doc/invoke.texi (-Wsuggest-attribute=const,
	-Wsuggest-attribute=pure): Document.
	* ipa-pure-const.c: Include toplev.h, intl.h and opts.h.
	(function_always_visible_to_compiler_p,
	suggest_attribute, warn_function_pure, warn_function_const):
	New functions.
	(check_call): Improve debug info.
	(analyze_function): Do not check availability.
	(add_new_function): Check availability.
	(propagate): Output warnings.
	(skip_function_for_local_pure_const): New function.
	(local_pure_const): Use it; output warnings.
	* common.opt (Wsuggest-attribute=const,
	Wsuggest-attribute=pure): New.

testsuite/
	* gcc.dg/pure-2.c: New testcase.
	* gcc.dg/const-1.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@158803 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 39e8fe7..0f376e5 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,21 @@
+2010-04-27  Manuel López-Ibáñez  <manu@gcc.gnu.org>
+           Jan Hubicka <hubicka@ucw.cz>
+
+       * doc/invoke.texi (-Wsuggest-attribute=const,
+       -Wsuggest-attribute=pure): Document.
+       * ipa-pure-const.c: Include toplev.h, intl.h and opts.h.
+       (function_always_visible_to_compiler_p,
+       suggest_attribute, warn_function_pure, warn_function_const):
+       New functions.
+       (check_call): Improve debug info.
+       (analyze_function): Do not check availability.
+       (add_new_function): Check availability.
+       (propagate): Output warnings.
+       (skip_function_for_local_pure_const): New function.
+       (local_pure_const): Use it; output warnings.
+       * common.opt (Wsuggest-attribute=const,
+       Wsuggest-attribute=pure): New.
+
 2010-04-27  Jakub Jelinek  <jakub@redhat.com>
 
        * dwarf2out.c (def_cfa_1): After DW_CFA_def_cfa_expression

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 23f744b..fefb0ab 100644 (file)
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -257,6 +257,7 @@ Objective-C and Objective-C++ Dialects}.
 -Wsign-compare  -Wsign-conversion  -Wstack-protector @gol
 -Wstrict-aliasing -Wstrict-aliasing=n @gol
 -Wstrict-overflow -Wstrict-overflow=@var{n} @gol
+-Wsuggest-attribute=@r{[}const@r{|}pure@r{]} @gol
 -Wswitch  -Wswitch-default  -Wswitch-enum -Wsync-nand @gol
 -Wsystem-headers  -Wtrigraphs  -Wtype-limits  -Wundef  -Wuninitialized @gol
 -Wunknown-pragmas  -Wno-pragmas @gol
@@ -3621,11 +3622,36 @@ comparisons, so this warning level will give a very large number of
 false positives.
 @end table
 
+@item -Wsuggest-attribute=@r{[}const@r{|}pure@r{]}
+@opindex Wsuggest-attribute=
+@opindex Wno-suggest-attribute=
+Warn for cases where adding an attribute may be beneficial. The
+attributes currently supported are listed below.
+
+@table @gcctabopt
+@item -Wsuggest-attribute=pure
+@itemx -Wsuggest-attribute=const
+@opindex Wsuggest-attribute=pure
+@opindex Wno-suggest-attribute=pure
+@opindex Wsuggest-attribute=const
+@opindex Wno-suggest-attribute=const
+
+Warn about functions which might be candidates for attributes
+@code{pure} or @code{const}.  The compiler only warns for functions
+visible in other compilation units or if it cannot prove that the
+function returns normally. A function returns normally if it doesn't
+contain an infinite loop nor returns abnormally by throwing, calling
+@code{abort()} or trapping.  This analysis requires option
+@option{-fipa-pure-const}, which is enabled by default at @option{-O}
+and higher.  Higher optimization levels improve the accuracy of the
+analysis.
+@end table
+
 @item -Warray-bounds
 @opindex Wno-array-bounds
 @opindex Warray-bounds
 This option is only active when @option{-ftree-vrp} is active
-(default for -O2 and above). It warns about subscripts to arrays
+(default for @option{-O2} and above). It warns about subscripts to arrays
 that are always out of bounds. This warning is enabled by @option{-Wall}.
 
 @item -Wno-div-by-zero

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3a32098..4a8fb18 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2010-04-27  Manuel López-Ibáñez  <manu@gcc.gnu.org>
+           Jan Hubicka <hubicka@ucw.cz>
+
+       * gcc.dg/pure-2.c: New testcase.
+       * gcc.dg/const-1.c: New testcase.
+
 2010-04-27  Jason Merrill  <jason@redhat.com>
 
        * g++.dg/cpp0x/lambda/lambda-ice1.C: New.