Make conversion warnings work on NULL with -ftrack-macro-expansion

There are various conversion related warnings that trigger on
potentially dangerous uses of NULL (or __null).  NULL is defined as a
macro in a system header, so calling warning or warning_at on a
virtual location of NULL yields no diagnostic.  So the test
accompanying this patch (as well as others), was failling when run
with -ftrack-macro-expansion.

I think it's necessary to use the location of NULL that is in the main
source code (instead of, e.g, the spelling location that is in the
system header where the macro is defined) in those cases.  Note that
for __null, we don't have the issue.

I have augmented the test of this patch to check that we don't regress
when handling __null.

Tested on x86_64-unknown-linux-gnu against trunk.

Note that the bootstrap with -ftrack-macro-expansion exhibits other
separate issues that are addressed in subsequent patches.  This patch
just fixes one class of problems.

The patch does pass bootstrap with -ftrack-macro-expansion turned off,
though.

gcc/
	* input.h (expansion_point_location_if_in_system_header): Declare
	new function.
	* input.c (expansion_point_location_if_in_system_header): Define it.
gcc/cp/

	* call.c (conversion_null_warnings): Use the new
	expansion_point_location_if_in_system_header.
	* cvt.c (build_expr_type_conversion): Likewise.
	* typeck.c (cp_build_binary_op): Likewise.

gcc/testsuite/

	* g++.dg/warn/Wconversion-null-2.C: Add testing for __null,
	alongside the previous testing for NULL.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186972 138bc75d-0d04-0410-961f-82ee72b054a4
Fix va_arg type location

Now that diagnostics first point to the spelling location of tokens
coming from macro expansion, the test case
gcc/testsuite/g++.old-deja/g++.other/vaarg3.C shows that when I write
va_args (args, some_type), the location that is recorded for
"some_type" is not correct.  We wrongly record a location that is in
the system header where the va_args macro is defined.

This patch changes that to correctly record the location for the type
operand of the va_arg expression.

With this patch applied, the
gcc/testsuite/g++.old-deja/g++.other/vaarg3.C test PASSes with and
without -ftrack-macro-expansion.

Tested on x86_64-unknown-linux-gnu against trunk.

Note that the bootstrap with -ftrack-macro-expansion exhibits other
separate issues that are addressed in subsequent patches.  This patch
just fixes one class of problems.

The patch does pass bootstrap with -ftrack-macro-expansion turned off,
though.

gcc/cp/

	* cp-tree.h (build_x_va_arg): Take an additional location
	parameter.
	* call.c (build_x_va_arg): Take a loc parameter for the location
	of the type of the va_arg expression.
	* parser.c (cp_parser_primary_expression): Pass the type of the
	type in the va_arg expression to build_x_va_arg.
	* pt.c (tsubst_copy): Adjust calls to build_x_va_arg.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186973 138bc75d-0d04-0410-961f-82ee72b054a4
Fix location for static class members

Consider the test case g++.dg/other/offsetof5.C:

    #include <stddef.h>

    struct A
    {
      char c;
      int &i;
    };

    int j = offsetof (A, i);		// { dg-warning "invalid access|offsetof" }

    template <typename T>
    struct S
    {
      T h;
      T &i;
      static const int j = offsetof (S, i);	// { dg-warning "invalid access|offsetof" }
    };

    int k = S<int>::j;			// { dg-message "required from here" }

The second warning (that involves the instantiation of the S template)
is not emitted when -ftrack-macro-expansion is on.

This is because during the instantiation of the member j of S
template, the location that is used for the warning is the one for the
DECL j (set by instantiate_decl).  And that location is inaccurately
set to the locus of 'offsetof', which is a macro defined in a system
header, so it's discarded by the diagnostics machinery.

Note that when we reach the point where we emit the warning in
build_class_member_access_expr offsetof expression has long been
folded, so we cannot use e.g, the location of the ')' token that would
have been in the source code.  So I believe the location of 'j' is the
best we can get at this point.

The patch below sets the location of the DECL for 'j' to what I
believe is its precise location; with that, the test case passes with
and without -ftrack-macro-expansion.  But I had to adjust
g++.dg/template/sfinae6_neg.C for that.

Tested on x86_64-unknown-linux-gnu against trunk.

gcc/cp

	* decl.c (grokdeclarator): Use the location carried by the
	declarator for the DECL of the static class member.

gcc/testsuite/

	* g++.dg/template/sfinae6_neg.C: Adjust.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186974 138bc75d-0d04-0410-961f-82ee72b054a4
Fix va_start related location

In gcc/testsuite/gcc.dg/pr30457.c, the first warning was not being
emitted because the relevant location was inside the var_start macro
defined in a system header.  It can even point to a token for a
builtin macro there.  This patch unwinds to the first token in real
source code in that case.

Tested on x86_64-unknown-linux-gnu against trunk.

	* builtins.c (fold_builtin_next_arg): Unwinds to the first
	location in real source code.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186975 138bc75d-0d04-0410-961f-82ee72b054a4
Adjust relevant test cases wrt -ftrack-macro-expansion=[0|2]

Even after all the patches I have already submitted, some test cases
where errors happens on tokens that are defined in macros see their
output change in an incompatible way, when you run them with or
without -ftrack-macro-expansion.

I think this is expected, because the (spelling) locus inside the
definition of the macro pointed to with -ftrack-macro-expansion is
different from the locus of the expansion point of the macro pointed
to without -ftrack-macro-expansion.

In those cases this patch either adjusts the test case and forces it
be run either with -ftrack-macro-expansion, or it just forces it to be
run without -ftrack-macro-expansion.

There are so many libstdc++ tests that were failing because of that
benign issue that I preferred to just run them with
-ftrack-macro-expansion diabled, after inspecting each of them to be
sure there was nothing more serious underneath.

Boostrapped on x86_64-unknown-linux-gnu against trunk with and without
-ftrack-macro-expansion turned on.

gcc/testsuite/

	* objc.dg/foreach-7.m: Force the test case to run without
	-ftrack-macro-expansion.
	* c-c++-common/tm/attrib-1.c: Likewise.
	* c-c++-common/warn-ommitted-condop.c: Likewise.
	* gcc.dg/assign-warn-1.c: Likewise.
	* gcc.dg/assign-warn-2.c: Likewise.
	* gcc.dg/attr-alloc_size.c: Likewise.
	* gcc.dg/builtin-stringop-chk-1.c: Likewise.
	* gcc.dg/builtin-stringop-chk-2.c: Likewise.
	* gcc.dg/builtin-strncat-chk-1.c: Likewise.
	* gcc.dg/c90-const-expr-9.c: Likewise.
	* gcc.dg/c99-const-expr-9.c: Likewise.
	* gcc.dg/cpp/direct2.c: Likewise.  Adjust.
	* gcc.dg/cpp/direct2s.c: Likewise.
	* gcc/testsuite/gcc.dg/cpp/pr28709.c: Likewise.
	* gcc.dg/cpp/pragma-diagnostic-1.c: Likewise.
	* gcc.dg/dfp/composite-type.c: Likewise.
	* gcc.dg/uninit-6-O0.c: Adjust the test case and force it to run
	with -ftrack-macro-expansion
	* g++.dg/cpp0x/constexpr-ex3.C: Likewise.
	* g++.dg/cpp0x/constexpr-overflow.C: Likewise.
	* g++.dg/ext/cleanup-1.C: Likewise.
	* g++.dg/ext/gnu-inline-global-reject.C: Likewise.
	* g++.dg/template/sfinae10.C: Likewise.
	* g++.dg/tm/wrap-2.C: Likewise.
	* g++.dg/warn/Wconversion-real-integer.C: Likewise.
	* g++.dg/warn/Wsign-conversion.C: Likewise.
	* g++.dg/warn/multiple-overflow-warn-1.C: Likewise.
	* g++.old-deja/g++.mike/p10769b.C: Likewise.
	* g++.dg/warn/Wdouble-promotion.C: Adjust the test case and force
	it to run with -ftrack-macro-expansion.
	* libstdc++-v3/scripts/testsuite_flags.in: By default, run the
	test cases without -ftrack-macro-expansion.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186976 138bc75d-0d04-0410-961f-82ee72b054a4
Switch -ftrack-macro-expansion=2 on by default.

This switches the compiler to -ftrack-macro-expansion=2 by default.

Tested and bootstrapped on x86_64-unknown-linux-gnu against trunk.

libcpp/

	* init.c (cpp_create_reader): Switch -ftrack-macro-expansion=2 on
	by default.  Add comments.

gcc/docs/

	* cppopts.texi: Adjust for enabling -ftrack-macro-expansion=2 by
	default.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186977 138bc75d-0d04-0410-961f-82ee72b054a4
Add -Wvarargs option

Several warnings related to questionable usage cases of variadic
function related macros (like va_start) could not be controlled by any
warning-related macro.  Fixed thus, by introducing the -Wvarargs
option.

Tested on x86_64-unknown-linux-gnu against trunk.

gcc/c-family/

	* c.opt (Wvarargs):  Define new option.

gcc/
	* builtins.c (fold_builtin_next_arg):  Use OPT_Wvarargs as an
	argument for the various warning_at calls.

gcc/doc/

	* invoke.texi: Update the documentation.

gcc/testsuite/

	* c-c++-common/Wvarargs.c: New test case.
	* c-c++-common/Wvarargs-2.c: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186978 138bc75d-0d04-0410-961f-82ee72b054a4
	* config/i386/i386.md (and<mode>3): Expand masking operations with
	0xff, 0xffff or 0xffffffff immediates to corresponding zero_extend RTX.
	(and splitter): Split to DImode zero_extend RTX for DImode operand[0].



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186979 138bc75d-0d04-0410-961f-82ee72b054a4
2012-04-30  Ian Bolton	<ian.bolton at arm.com>
	    Sameera Deshpande  <sameera.deshpande at arm.com>
	    Greta Yorsh	 <greta.yorsh at arm.com>

	* config/arm/arm-protos.h (ldm_stm_operation_p): New declaration.
	* config/arm/arm.c (ldm_stm_operation_p): New function.
	* config/arm/predicates.md (load_multiple_operation): Update predicate.
	(store_multiple_operation): Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186980 138bc75d-0d04-0410-961f-82ee72b054a4
2012-04-24  Ian Bolton  <ian.bolton at arm.com>
            Sameera Deshpande  <sameera.deshpande at arm.com>
            Greta Yorsh  <greta.yorsh at arm.com>

        * config/arm/arm-protos.h (ldm_stm_operation_p): New parameters.
        * config/arm/arm.c (ldm_stm_operation_p): New parameters.
        * config/arm/predicates.md (load_multiple_operation): Add arguments.
        (store_multiple_operation): Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186981 138bc75d-0d04-0410-961f-82ee72b054a4
Fix email addresses


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186982 138bc75d-0d04-0410-961f-82ee72b054a4
2012-04-30  Andrew Stubbs  <ams@codesourcery.com>

	* config/arm/arm.c (neon_valid_immediate): Allow const_int.
	(arm_print_operand): Add 'x' format.
	* config/arm/constraints.md (Dn): Allow const_int.
	* config/arm/neon.md (neon_mov<mode>): Use VDX to allow DImode.
	Use 'x' format to print constants.
	* config/arm/predicates.md (imm_for_neon_mov_operand): Allow const_int.
	* config/arm/vfp.md (movdi_vfp): Disable for const_int when neon
	is enabled.
	(movdi_vfp_cortexa8): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186983 138bc75d-0d04-0410-961f-82ee72b054a4
2012-04-30  Andrew Stubbs  <ams@codesourcery.com>

	* config/arm/arm.md (negdi2): Use gen_negdi2_neon.
	* config/arm/neon.md (negdi2_neon): New insn.
	Also add splitters for core and NEON registers.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186984 138bc75d-0d04-0410-961f-82ee72b054a4
Fix failure in gcc.dg/pr52283.c by adding the missing
dg-warning and dg-options.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186985 138bc75d-0d04-0410-961f-82ee72b054a4
	PR go/52586
mksysinfo, syscall: Make sure SYS_GETDENTS64 is defined.

Fixes build on MIPS GNU/Linux.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186986 138bc75d-0d04-0410-961f-82ee72b054a4
	PR c++/51314
	* parser.c (cp_parser_sizeof_operand): Require parentheses for
	sizeof...

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186988 138bc75d-0d04-0410-961f-82ee72b054a4
	* dwarf2out.c (comdat_symbol_id): Add const.
	(union die_symbol_or_type_node): Add const to die_symbol.
	(output_die_symbol, output_die, output_comp_unit): Adjust.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186989 138bc75d-0d04-0410-961f-82ee72b054a4
        * config/arm/arm.md (UNSPEC_LL): New.
        * config/arm/sync.md (atomic_loaddi, atomic_loaddi_1): New.
        (arm_load_exclusivedi): Use %H0.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186990 138bc75d-0d04-0410-961f-82ee72b054a4
2012-04-30  Manuel López-Ibáñez  <manu@gcc.gnu.org>
	    Dodji Seketeli  <dodji@seketeli.org>

	PR c++/52974
	* libcpp/files.c (maybe_shorter_path): New.
	(find_file_in_dir): Use it.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186991 138bc75d-0d04-0410-961f-82ee72b054a4
 * libcpp/ChangeLog: Fix PR number.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@186992 138bc75d-0d04-0410-961f-82ee72b054a4