gcc/testsuite/ChangeLog:
	* gcc.dg/Wvla-parameter-2.c: Use unique strings in directive names.

gcc/
	* config/bfin/bfin.h (NOTICE_UPDATE_CC): Remove.

Checking for an osc break is somewhat brittle especially with many
passes potentially introducing new insns and moving them around.
Therefore, only compile the test with -O1 -fschedule-insns in order
to limit the influence of other passes.

gcc/testsuite/ChangeLog:

	* gcc.target/s390/oscbreak-1.c: Compile with -O1
	-fschedule-insns

This removes CC0 and all directly related infrastructure.

CC_STATUS, CC_STATUS_MDEP, CC_STATUS_MDEP_INIT, and NOTICE_UPDATE_CC
are deleted and poisoned.  CC0 is only deleted (some targets use that
name for something else).  HAVE_cc0 is automatically generated, and we
no longer will do that after this patch.

CC_STATUS_INIT is suggested in final.c to also be useful for ports that
are not CC0, and at least arm seems to use it for something.  So I am
leaving that alone, but most targets that have it could remove it.

2021-05-04  Segher Boessenkool  <segher@kernel.crashing.org>

	* caller-save.c: Remove CC0.
	* cfgcleanup.c: Remove CC0.
	* cfgrtl.c: Remove CC0.
	* combine.c: Remove CC0.
	* compare-elim.c: Remove CC0.
	* conditions.h: Remove CC0.
	* config/h8300/h8300.h: Remove CC0.
	* config/h8300/h8300-protos.h: Remove CC0.
	* config/h8300/peepholes.md: Remove CC0.
	* config/i386/x86-tune-sched.c: Remove CC0.
	* config/m68k/m68k.c: Remove CC0.
	* config/rl78/rl78.c: Remove CC0.
	* config/sparc/sparc.c: Remove CC0.
	* config/xtensa/xtensa.c: Remove CC0.
	(gen_conditional_move):  Use pc_rtx instead of cc0_rtx in a piece of
	RTL where that is used as a placeholder only.
	* cprop.c: Remove CC0.
	* cse.c: Remove CC0.
	* cselib.c: Remove CC0.
	* df-problems.c: Remove CC0.
	* df-scan.c: Remove CC0.
	* doc/md.texi: Remove CC0.  Adjust an example.
	* doc/rtl.texi: Remove CC0.  Adjust an example.
	* doc/tm.texi: Regenerate.
	* doc/tm.texi.in: Remove CC0.
	* emit-rtl.c: Remove CC0.
	* final.c: Remove CC0.
	* fwprop.c: Remove CC0.
	* gcse-common.c: Remove CC0.
	* gcse.c: Remove CC0.
	* genattrtab.c: Remove CC0.
	* genconfig.c: Remove CC0.
	* genemit.c: Remove CC0.
	* genextract.c: Remove CC0.
	* gengenrtl.c: Remove CC0.
	* genrecog.c: Remove CC0.
	* haifa-sched.c: Remove CC0.
	* ifcvt.c: Remove CC0.
	* ira-costs.c: Remove CC0.
	* ira.c: Remove CC0.
	* jump.c: Remove CC0.
	* loop-invariant.c: Remove CC0.
	* lra-constraints.c: Remove CC0.
	* lra-eliminations.c: Remove CC0.
	* optabs.c: Remove CC0.
	* postreload-gcse.c: Remove CC0.
	* postreload.c: Remove CC0.
	* print-rtl.c: Remove CC0.
	* read-rtl-function.c: Remove CC0.
	* reg-notes.def: Remove CC0.
	* reg-stack.c: Remove CC0.
	* reginfo.c: Remove CC0.
	* regrename.c: Remove CC0.
	* reload.c: Remove CC0.
	* reload1.c: Remove CC0.
	* reorg.c: Remove CC0.
	* resource.c: Remove CC0.
	* rtl.c: Remove CC0.
	* rtl.def: Remove CC0.
	* rtl.h: Remove CC0.
	* rtlanal.c: Remove CC0.
	* sched-deps.c: Remove CC0.
	* sched-rgn.c: Remove CC0.
	* shrink-wrap.c: Remove CC0.
	* simplify-rtx.c: Remove CC0.
	* system.h: Remove CC0.  Poison NOTICE_UPDATE_CC, CC_STATUS_MDEP_INIT,
	CC_STATUS_MDEP, and CC_STATUS.
	* target.def: Remove CC0.
	* valtrack.c: Remove CC0.
	* var-tracking.c: Remove CC0.

phiopt now has dominator queries but fails to compute dominance
info.

2021-05-04  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/100414
	* tree-ssa-phiopt.c (get_non_trapping): Do not compute dominance
	info here.
	(tree_ssa_phiopt_worker): But unconditionally here.

	* gcc.dg/pr100414.c: New testcase.

C/C++ permit logical AND and logical OR also with floating-point or complex
arguments by doing an unequal zero comparison; the result is an 'int' with
value one or zero.  Hence, those are also permitted as reduction variable,
even though it is not the most sensible thing to do.

gcc/c/ChangeLog:

	* c-typeck.c (c_finish_omp_clauses): Accept float + complex
	for || and && reductions.

gcc/cp/ChangeLog:

	* semantics.c (finish_omp_reduction_clause): Accept float + complex
	for || and && reductions.

gcc/ChangeLog:

	* omp-low.c (lower_rec_input_clauses, lower_reduction_clauses): Handle
	&& and || with floating-point and complex arguments.

gcc/testsuite/ChangeLog:

	* gcc.dg/gomp/clause-1.c: Use 'reduction(&:..)' instead of '...(&&:..)'.

libgomp/ChangeLog:

	* testsuite/libgomp.c-c++-common/reduction-1.c: New test.
	* testsuite/libgomp.c-c++-common/reduction-2.c: New test.
	* testsuite/libgomp.c-c++-common/reduction-3.c: New test.

2021-05-04  Nick Clifton  <nickc@redhat.com>

	* configure.ac (AC_PROG_CC): Replace with AC_PROG_CC_C99.
	* configure: Regenerate.

This avoids errors outside the immediate context when std::visit is an
overload candidate because of ADL, but not actually viable.

The solution is to give std::visit a non-deduced return type. New
helpers are introduced for that, and existing ones refactored slightly.

libstdc++-v3/ChangeLog:

	PR libstdc++/100384
	* include/std/variant (__get_t): New alias template yielding the
	return type of std::get<N> on a variant.
	(__visit_result_t): New alias template yielding the result of
	std::visit.
	(__same_types): Move into namespace __detail::__variant.
	(__check_visitor_results): Likewise. Use __invoke_result_t and
	__get_t.
	(__check_visitor_result): Remove.
	(visit): Use __visit_result_t for return type.
	* testsuite/20_util/variant/100384.cc: New test.

We don't need to decide whether to use __int128 when running configure,
we can do so at compilation time by seeing if __SIZEOF_INT128__ is
defined and if it's greater than __SIZEOF_LONG_LONG__.

This removes another unnecessary architecture-specific config macro in
<bits/c++config.h>, so the same header can work for 32-bit or 64-bit
compilation on AIX.

libstdc++-v3/ChangeLog:

	* acinclude.m4 (GLIBCXX_ENABLE_INT128_FLOAT128): Remove
	checks for __int128 and rename to GLIBCXX_ENABLE_FLOAT128.
	* config.h.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Adjust to use GLIBCXX_ENABLE_FLOAT128.
	* include/bits/random.h (_Select_uint_least_t<s, 1>):
	Use __SIZEOF_INT128__ to decide whether to use __int128.
	* include/std/charconv (__to_chars_unsigned_type): Likewise.

When a call to a function is inlined and takes a parameter whose type is not
gimple_reg, a local variable is created in the caller to hold a copy of the
argument passed in the call with the following comment:

      /* We may produce non-gimple trees by adding NOPs or introduce
         invalid sharing when operand is not really constant.
         It is not big deal to prohibit constant propagation here as
         we will constant propagate in DOM1 pass anyway.  *

Of course the second sentence of the comment does not apply to non-gimple_reg
values, unless they get SRAed later, because we don't do constant propagation
for them.  This for example prevents two identical calls to a pure function
from being merged in the attached Ada testcase.

Therefore the attached patch attempts to reuse a read-only or non-addressable
local DECL of the caller, the hitch being that expand_call_inline needs to be
prevented from creating a CLOBBER for the case where it ends uo being reused.

gcc/
	* tree-inline.c (insert_debug_decl_map): Delete.
	(copy_debug_stmt): Minor tweak.
	(setup_one_parameter): Do not use a variable if the value is either
	a read-only DECL or a non-addressable local variable in the caller.
	In this case, insert the debug-only variable in the map manually.
	(expand_call_inline): Do not generate a CLOBBER for these values.
	* tree-inline.h (debug_map): Minor tweak.

The test for the presence of variables (really symbols) does not work
when you add -Ox -flto to CFLAGS:

  for v in $vars; do
    AC_MSG_CHECKING([for $v])
    AC_CACHE_VAL(libiberty_cv_var_$v,
      [AC_LINK_IFELSE([AC_LANG_PROGRAM([[int *p;]],[[extern int $v [];
                                         p = $v;]])],
                      [eval "libiberty_cv_var_$v=yes"],
                      [eval "libiberty_cv_var_$v=no"])])
    if eval "test \"`echo '$libiberty_cv_var_'$v`\" = yes"; then
      AC_MSG_RESULT(yes)
      AC_DEFINE_UNQUOTED($n)
    else
      AC_MSG_RESULT(no)
    fi
  done

because the assignment to 'p' is optimized away by LTO.  This is visible
on MinGW platforms in the form of a link failure for sys_siglist.

There is another link failures for stpcpy: the symbol is both referenced
by libiberty's pex-win32.c and provided by libiberty's stpcpy.c, so it
needs to have a linkage to be resolved in LTO mode.

libiberty/
	* configure.ac: Make test for variables more robust.
	* configure: Regenerate.
gcc/
	* builtins.c (builtin_with_linkage_p): Return true for stp[n]cpy.
	* symtab.c (symtab_node::output_to_lto_symbol_table_p): Tidy up.

This restricts the testcase to the target where it exposes the
situation fixed with g:e9d297a1
which targets BIT_FIELD_REFs created by fold_truth_andor.

This avoids strange dejagnu limits with overly long target lists
and simplifies the tests.

2021-05-04  Richard Biener  <rguenther@suse.de>

	* gcc.dg/tree-ssa/ssa-dse-26.c: Skip on !lp64 targets,
	simplify dump scanning down to one case.

This avoids reassociating asm goto defs because we have no idea
on which outgoing edge to insert defs.

2021-05-04  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/100329
	* tree-ssa-reassoc.c (can_reassociate_p): Do not reassociate
	asm goto defs.
	(insert_stmt_after): Assert we're not running into asm goto.

	* gcc.dg/torture/pr100329.c: New testcase.

The following makes sure to preserve control altering stmts
when removing trivially dead stmts in DSE.

2021-05-04  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/100398
	* tree-ssa-dse.c (pass_dse::execute): Preserve control
	altering stmts.

	* gcc.dg/torture/pr100398.c: New testcase.

gcc/ada/

	* pprint.adb: Remove qualification of arbitrary calls to
	Sinfo.Expressions and Sinfo.Parameter_Associations.

gcc/ada/

	* pprint.adb (Expr_Name): Simplify with functional variant of
	UI_Image.

gcc/ada/

	* pprint.adb (To_Mixed): Removed.

gcc/ada/

	* pprint.adb (List_Name_Count): Change type from Integer to
	Natural.

gcc/ada/

	* pprint.adb (Expression_Image): Special case for
	expression-with-actions.

gcc/ada/

	* exp_ch4.adb (Expand_Concatenate): Remove the non-optimization.

gcc/ada/

	* lib-xref.adb (Generate_Reference_To_Formals): Remove dedicated
	branch for generic subprograms (they are now handled together
	with non-generic subprograms in the ELSE branch); replace a
	low-level Ekind membership test with a high-level call to
	Is_Access_Subprogram_Type.

gcc/ada/

	* sem_ch12.adb (Check_Abstract_Primitives): Match First_Formal
	with Next_Formal.
	* sem_ch6.adb (Is_Non_Overriding_Operation): Likewise.

gcc/ada/

	* sem_prag.adb (Collect_Global_Item): Iterate directly over
	formals.

gcc/ada/

	* sem_prag.ads (Collect_Subprogram_Inputs_Outputs): Update
	comment; this routine is no longer used by GNATprove.
	* sem_prag.adb (Find_Role): The IN parameter is on output only
	when it belongs to non-function; also, the otherwise constant
	object can only be written by a non-function.
	(Collect_Global_Item): The IN parameter can only be written when
	it belongs to non-function; also, unnest this check to make it
	easier to read.

gcc/ada/

	* libgnat/s-assert.ads (Assert_Failure): Now a renaming of
	Assertion_Error.
	* libgnat/a-assert.ads (Assertion_Error): Now a first class
	citizen.  Remove dependency on System.Assertions.
	* gcc-interface/a-assert.ads, gcc-interface/a-assert.adb: New.
	* gcc-interface/Make-lang.in (GNAT_ADA_OBJS, GNATBIND_OBJS): Add
	a-assert.o from gcc-interface.

gcc/ada/

	* erroutc.adb (Matches): Move spec...
	* erroutc.ads (Matches): ...here.

gcc/ada/

	* gnat1drv.adb (Adjust_Global_Switches): Force error marker in
	GNATprove mode.

gcc/ada/

	* binde.adb: No need for ??? marks in Binde, because it is
	superseded by Bindo.
	* bindo-writers.adb (Write_Unit_Closure): Verified that -Ra
	works.
	* exp_ch4.adb, sinfo.ads (Expand_N_Type_Conversion): Rules for
	conversions passed to gigi are documented in sinfo.ads.
	(Expand_N_Unchecked_Type_Conversion): Comment is a duplicate of
	one in sinfo.ads.
	(Expand_N_In): Robert already added sufficient comments years
	after the ??? comment was inserted.
	(Expand_Membership_Minimize_Eliminate_Overflow): I don't see any
	reason why Stand should export Long_Long_Integer'Base -- it
	doesn't export any other base types.
	(Size_In_Storage_Elements): We are doing an allocator, so we
	don't care about sizes in bits.
	(Expand_N_Allocator): PolyORB isn't going to be significantly
	improved, so we're not going to mess with remote access to
	class-wide types.
	(Optimize_Return_Stmt): It's not important to optimize return
	statements in predicate functions -- there are many
	more-important optimizations we could do. Keep part of the
	comment without "???", to clarify why the "and then ...".
	(User_Defined_Primitive_Equality_Op): The optimization doesn't
	seem important enough.
	(Expand_N_Unchecked_Type_Conversion): Refactor to use
	Expand_N_Unchecked_Expression.
	(Make_Array_Comparison_Op): This seems like a case of "it it's
	not broken, don't fix it". Too much risk of causing bugs.
	* debug_a.adb: Remove ??? comments asking why Current_Error_Node
	is maintained unconditionally, and add a comment explaining why.
	* errout.adb: These kinds of minor bugs do indeed exist, but
	we're never going to get around to fixing them "properly", so we
	need this code for robustness.
	* gnatchop.adb (Read_File): Document when read can fail.
	* gnatdll.adb (Parse_Command_Line): Nobody is complaining about
	these arbitrary limits, so no need to use Table. Increase the
	limits just in case.  It is clear from the names what they are
	limits on.
	* gnatlink.adb: Add needed comments.
	(Delete): An existing comment makes clear it's intentional, and
	it's been like that since 1996.
	(Process_Args): Improve comments.
	(Search_Library_Path): Refactoring to avoid deep nesting.
	* inline.adb (Build_Body_To_Inline): Probably won't get around
	to doing that optimization.
	(Is_Unit_Subprogram): No, this should not be moved to Sem_Aux,
	because it is too specialized to this context.
	(Do_Reset): No comment is needed here; it's clear from the
	comment on Reset_Dispatching_Calls. Do_Reset is an artificial
	subprogram; if we had proper iterators, it would just be an if
	statement in the loop.
	(Rewrite_Function_Call): Probably won't get around to doing that
	optimization.
	* layout.adb (Layout_Type): The gigi comment doesn't need to be
	a ??? comment, and it's been that way since 2000.  The
	limitation to scalars will likely never be investigated, and
	it's been that way since 2009.
	* lib.adb (Check_Same_Extended_Unit): This doesn't look like
	something that needs fixing; it looks like a permanent
	workaround.
	* lib-load.adb (Change_Main_Unit_To_Spec): It is good enough in
	practice.
	(Load_Unit): Nobody will ever get around to investigating the
	obscure PMES oddity, and the optimization is not worth the
	trouble.
	* live.adb: It's not worth documenting this. It is used only
	with a debug switch. Nobody who has done significant work on it
	is still around, so it would require substantial investigation.
	* mdll.ads: I see no reason for USE.
	* namet.ads: Routines are obsolete, but they're not going
	anywhere anytime soon (too much work, and surprisingly delicate
	because of dependences on global variables).
	* osint.ads: Minor.
	* osint.adb: Improve comments.
	(Full_Lib_File_Name): Use Smart_Find_File.

gcc/ada/

	* exp_prag.adb, sem_prag.adb: Replace low-level Ekind membership
	tests with a high-level call to Is_Formal_Object.

gcc/ada/

	* cstand.adb, sprint.adb, switch-c.adb, xr_tabls.ads,
	xr_tabls.adb, xref_lib.adb: Address ??? comments.

gcc/ada/

	* sem_prag.adb (Analyze_Global_Item): Take subprogram kind into
	account when accepting or rejecting a constant of an
	access-to-variable type as a global Output/In_Out; do this check
	inside an ELSIF branch to avoid unnecessary evaluation of the
	subsequent condition.

gcc/ada/

	* sem_prag.adb (Role_Error, Usage_Error): Replace calls to
	Name_Find and Get_Name_String with a call to To_String.

gcc/ada/

	* exp_aggr.adb (Build_Siz_Exp): new function, subsidiary of
	Expand_Container_Aggregate, to create an expression to be used
	in the dynamic allocation of a container with a single container
	element association.
	(Add_Range): Handle static bounds of ranges over enumerations.
	(Expand_Container_Aggregate): Add declaration for size
	expression when needed, and use it in container object
	declaration for container.

gcc/ada/

	* exp_ch7.adb (Build_Finalizer_Helper.New_Finalizer_Name):
	Unnest so that it can be reused.
	(Build_Finalizer_Helper.Process_Declarations): Call the
	xxx__finalize_body procedure of a package instantiation in case
	it contains finalization statements.  Code clean ups.
	(Build_Finalizer_Helper.Create_Finalizer): Export and set an
	Interface_Name for library level finalizers since these may be
	imported now.
	(Build_Finalizer_Helper): Need to process library level package
	body instantiations which may contain objects requiring
	finalization.
	* libgnat/s-finmas.ads: Fix typo.

gcc/ada/

	* checks.adb (Append_Range_Checks, Apply_Selected_Length_Checks,
	Determine_Range, Insert_Range_Checks,
	Install_Null_Excluding_Check, Selected_Length_Checks,
	Selected_Range_Checks): Address ??? comments and code cleanups.

gcc/ada/

	* sem_prag.adb (Check_Mode_Restriction_In_Enclosing_Context):
	Apply the rule even with no explicit Global contract (and remove
	a dead condition for Refined_Global).

gcc/ada/

	* sem_prag.adb (Check_Mode_Restriction_In_Enclosing_Context):
	Extend check to protected entries.

gcc/ada/

	* sem_prag.adb (Check_Mode_Restriction_In_Enclosing_Context):
	Fix reference to SPARK RM rule number.

gcc/ada/

	* exp_intr.adb: Remove with/use clauses for Urealp.
	(Expand_Is_Negative): Delete.
	(Expand_Intrinsic_Call): Do not call it.
	* rtsfind.ads (RE_Id): Remove RE_Float_Unsigned.
	(RE_Unit_Table): Remove entry for RE_Float_Unsigned.
	* snames.ads-tmpl (Name_Is_Negative): Delete.
	* libgnat/s-imgrea.ads (Set_Image_Real): Fix mode of S parameter.
	* libgnat/s-imgrea.adb: Add with/use clauses for System.Img_Util.
	(LLU): New subtype.
	(Maxdigs): Use it.
	(Is_Negative): Reimplement.
	(Image_Floating_Point): Simplify.
	(Set_Image_Real): Fix mode of S parameter.  Remove the low-level
	processing on characters.  Flip the sign of the Scale variable.
	Compute the maximum number of digits for the straight notation.
	Call Set_Decimal_Digits at the end to do the final formatting.
	* libgnat/s-imguti.ads (Floating_Invalid_Value): New type.
	(Set_Floating_Invalid_Value): New procedure.
	* libgnat/s-imguti.adb (Set_Floating_Invalid_Value): Implement it
	based on existing code from Set_Image_Real.
	* libgnat/s-unstyp.ads (Float_Unsigned): Delete.

gcc/ada/

	* csets.adb (Initialize): Refactor into CASE statement; raise
	exception on unsupported code of character set (it will be
	gently rejected earlier when scanning command line switches).
	* switch-b.adb (Scan_Binder_Switches): Refactor into a
	membership expression; add missing '9' choice; reorder as
	described by GNAT UG, section 4.3.11.
	* switch-c.adb (Scan_Front_End_Switches): Refactor into a
	membership expression and reorder as above.
	* doc/gnat_ugn/building_executable_programs_with_gnat.rst
	(gnatic): Mention '5' as an allowed value for "c".
	* gnat_ugn.texi: Regenerate.