The libiberty hash table includes a helper function for strings, but
no equality function.  Consequently, this equality function has been
reimplemented a number of times in both the gcc and binutils-gdb
source trees.  This patch adds the function to the libiberty hash
table, as a step toward the goal of removing all the copies.

One change to gcc is included here.  Normally I would have put this in
the next patch, but gensupport.c used the most natural name for its
reimplementation of this function, and this can't coexist with the
extern function in libiberty.

include

	* hashtab.h (htab_eq_string): Declare.

libiberty

	* hashtab.c (htab_eq_string): New function.

gcc

	* gensupport.c (htab_eq_string): Remove.

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.

Sync with binutils for PR binutils/27397.  Check if host supports
multi-byte NOPs before enabling CET on host.

config/

	PR bootstrap/99703
	* cet.m4 (GCC_CET_HOST_FLAGS): Check if host supports multi-byte
	NOPs.

libiberty/

	PR bootstrap/99703
	* configure: Regenerated.

libiberty/
	PR demangler/100177
	* rust-demangle.c (demangle_const_char): Properly print the
	character value.

r11-4926 made __alignof__ get mangled differently from alignof,
encoding __alignof__ as a vendor extended operator.  But this
mangling is problematic for the reasons mentioned in
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88115#c6.

This patch changes our mangling of __alignof__ to instead use the
new "vendor extended expression" syntax that's proposed in
https://github.com/itanium-cxx-abi/cxx-abi/issues/112.  Clang does
the same thing already, so after this patch Clang and GCC agree
about the mangling of __alignof__(type) and __alignof__(expr).

gcc/cp/ChangeLog:

	PR c++/88115
	* mangle.c (write_expression): Adjust the mangling of
	__alignof__.

include/ChangeLog:

	PR c++/88115
	* demangle.h (enum demangle_component_type): Add
	DEMANGLE_COMPONENT_VENDOR_EXPR.

libiberty/ChangeLog:

	PR c++/88115
	* cp-demangle.c (d_dump, d_make_comp, d_expression_1)
	(d_count_templates_scopes): Handle DEMANGLE_COMPONENT_VENDOR_EXPR.
	(d_print_comp_inner): Likewise.
	<case DEMANGLE_COMPONENT_EXTENDED_OPERATOR>: Revert r11-4926
	change.
	<case DEMANGLE_COMPONENT_UNARY>: Likewise.
	* testsuite/demangle-expected: Adjust __alignof__ tests.

gcc/testsuite/ChangeLog:

	PR c++/88115
	* g++.dg/cpp0x/alignof7.C: Adjust expected mangling.

libiberty/
	* sha1.c (sha1_process_bytes): Use memmove in place of memcpy.

Move custom macros to acinclude.m4 so we can autogenerate aclocal.m4
with aclocal.  This matches every other project in the tree.

libiberty/ChangeLog:

	* Makefile.in (ACLOCAL, ACLOCAL_AMFLAGS, $(srcdir)/aclocal.m4): Define.
	(configure_deps): Rename to ...
	(aclocal_deps): ... this.  Replace aclocal.m4 with acinclude.m4.
	($(srcdir)/configure): Replace $(configure_deps) with
	$(srcdir)/aclocal.m4.
	* aclocal.m4: Move libiberty macros to acinclude.m4, then regenerate.
	* acinclude.m4: New file.
	* configure: Regenerate.

libiberty:
	* argv.c (expandargv): free allocated buffer if read fails.

libiberty/ChangeLog:

	* dyn-string.c (dyn_string_insert_cstr): Use memcpy instead of strncpy
	to avoid -Wstringop-truncation.

libiberty/ChangeLog:

	* strverscmp.c: Convert to utf8 from iso8859.

gcc/testsuite/ChangeLog:

	* README: Convert to utf8 from iso8859.

The ABI for unresolved scoped names on the RHS of . and -> used to be

  sr <type> <unqualified-id>

That changed years ago to something more complex, but G++ was never updated.
This change was particularly incompatible for simple qualified-ids like
A::x, which were previously mangled as sr1A1x, and now sr1AE1x.

This obviously makes life hard for demanglers, which can't know whether to
consume that E or not.  To work around this, we now try demangling with the
newer ABI, and if that fails and we saw an "sr", try again with the older
ABI.

libiberty/ChangeLog:

	PR c++/67343
	* cp-demangle.h (struct d_info): Add unresolved_name_state.
	* cp-demangle.c (d_prefix): Add subst parm.
	(d_nested_name): Pass it.
	(d_unresolved_name): Split out from...
	(d_expression_1): ...here.
	(d_demangle_callback): Maybe retry with old sr mangling.
	* testsuite/demangle-expected: Add test.

The demangler was assuming that only an unqualified-id could appear after
. or ->.

libiberty/ChangeLog:

	* cp-demangle.c (d_expression_1): Recognize qualified-id
	on RHS of dt/pt.
	* testsuite/demangle-expected: Add test.

d_operator_name decides whether "cv" indicates a cast or a conversion
operator based on is_expression.  "on" specifies that we want the conversion
operator.

libiberty/ChangeLog:

	* cp-demangle.c (d_unqualified_name): Clear is_expression.
	* testsuite/demangle-expected: Add tests.

This is an analogous option to --bootstrap-asan to configure.  It allows
bootstrapping GCC using HWASAN.

For the same reasons as for ASAN we have to avoid using the HWASAN
sanitizer when compiling libiberty and the lto-plugin.

Also add a function to query whether -fsanitize=hwaddress has been
passed.

ChangeLog:

	* configure: Regenerate.
	* configure.ac: Add --bootstrap-hwasan option.

config/ChangeLog:

	* bootstrap-hwasan.mk: New file.

gcc/ChangeLog:

	* doc/install.texi: Document new option.

libiberty/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Avoid using sanitizer.

lto-plugin/ChangeLog:

	* Makefile.am: Avoid using sanitizer.
	* Makefile.in: Regenerate.

This is the libiberty (mainly for binutils/gdb) counterpart of
https://github.com/alexcrichton/rustc-demangle/pull/23.

Relevant links for the new Rust mangling scheme (aka "v0"):
* Rust RFC: https://github.com/rust-lang/rfcs/pull/2603
* tracking issue: https://github.com/rust-lang/rust/issues/60705
* implementation: https://github.com/rust-lang/rust/pull/57967

This implementation includes full support for UTF-8 identifiers
via punycode, so I've included a testcase for that as well.

libiberty/ChangeLog:
	* rust-demangle.c (struct rust_demangler): Add
	skipping_printing and bound_lifetime_depth fields.
	(eat): Add (v0-only).
	(parse_integer_62): Add (v0-only).
	(parse_opt_integer_62): Add (v0-only).
	(parse_disambiguator): Add (v0-only).
	(struct rust_mangled_ident): Add punycode{,_len} fields.
	(parse_ident): Support v0 identifiers.
	(print_str): Respect skipping_printing.
	(print_uint64): Add (v0-only).
	(print_uint64_hex): Add (v0-only).
	(print_ident): Respect skipping_printing,
	Support v0 identifiers.
	(print_lifetime_from_index): Add (v0-only).
	(demangle_binder): Add (v0-only).
	(demangle_path): Add (v0-only).
	(demangle_generic_arg): Add (v0-only).
	(demangle_type): Add (v0-only).
	(demangle_path_maybe_open_generics): Add (v0-only).
	(demangle_dyn_trait): Add (v0-only).
	(demangle_const): Add (v0-only).
	(demangle_const_uint): Add (v0-only).
	(basic_type): Add (v0-only).
	(rust_demangle_callback): Support v0 symbols.
	* testsuite/rust-demangle-expected: Add v0 testcases.

libiberty/

	* strstr.c (strstr): Make implementation ANSI/POSIX compliant.

This patch changes the mangling of __alignof__ to v111__alignof__,
making its mangling distinct from that of alignof(type) and
alignof(expr).

How we mangle ALIGNOF_EXPR now depends on its ALIGNOF_EXPR_STD_P flag,
which after the previous patch gets consistently set for alignof(type)
as well as alignof(expr).

gcc/c-family/ChangeLog:

	PR c++/88115
	* c-opts.c (c_common_post_options): Update latest_abi_version.

gcc/ChangeLog:

	PR c++/88115
	* common.opt (-fabi-version): Document =15.
	* doc/invoke.texi (C++ Dialect Options): Likewise.

gcc/cp/ChangeLog:

	PR c++/88115
	* mangle.c (write_expression): Mangle __alignof_ differently
	from alignof when the ABI version is at least 15.

libiberty/ChangeLog:

	PR c++/88115
	* cp-demangle.c (d_print_comp_inner)
	<case DEMANGLE_COMPONENT_EXTENDED_OPERATOR>: Don't print the
	"operator " prefix for __alignof__.
	<case DEMANGLE_COMPONENT_UNARY>: Always print parens around the
	operand of __alignof__.
	* testsuite/demangle-expected: Test demangling for __alignof__.

gcc/testsuite/ChangeLog:

	PR c++/88115
	* g++.dg/abi/macro0.C: Adjust.
	* g++.dg/cpp0x/alignof7.C: New test.
	* g++.dg/cpp0x/alignof8.C: New test.

Initializing orig_err avoids a warning: "may be used uninitialized".
See 97108.

2020-09-14  Torbjörn SVENSSON <torbjorn.svensson@st.com>
	Christophe Lyon  <christophe.lyon@linaro.org>

	libiberty/
	* pex-win32.c (pex_win32_exec_child): Initialize orig_err.

readelf -S prints:

There are 81999 section headers, starting at offset 0x1f488060:

Section Headers:
  [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
  [ 0]                   NULL            0000000000000000 000000 01404f 00     81998   0  0
  [ 1] .group            GROUP           0000000000000000 000040 000008 04     81995 105027  4
...
  [81995] .symtab           SYMTAB          0000000000000000 d5d9298 2db310 18     81997 105026  8
  [81996] .symtab_shndx     SYMTAB SECTION INDICES 0000000000000000 d8b45a8 079dd8 04     81995   0  4
  [81997] .strtab           STRTAB          0000000000000000 d92e380 80460c 00      0   0  1
...

Looking at the documentation:
Table 7–15 ELF sh_link and sh_info Interpretation

sh_type - sh_link
SHT_SYMTAB - The section header index of the associated string table.
SHT_SYMTAB_SHNDX - The section header index of the associated symbol table.

As seen, sh_link of a SHT_SYMTAB always points to a .strtab and readelf
confirms that.

So we need to use reverse mapping taken from
  [81996] .symtab_shndx     SYMTAB SECTION INDICES 0000000000000000 d8b45a8 079dd8 04     81995   0  4

where sh_link points to 81995.

libiberty/ChangeLog:

	PR lto/97290
	* simple-object-elf.c (simple_object_elf_copy_lto_debug_sections):
	Use sh_link of a .symtab_shndx section.

This adds a get_DW_UT_name function to dwarfnames using dwarf2.def
for use in binutils readelf to show the unit types in a DWARF5 header.

Also remove DW_CIE_VERSION which was already removed in binutils/gdb
and is not used in gcc.

include/ChangeLog:

	* dwarf2.def: Add DWARF5 Unit type header encoding macros
	DW_UT_FIRST, DW_UT and DW_UT_END.
	* dwarf2.h (enum dwarf_unit_type): Removed and define using
	DW_UT_FIRST, DW_UT and DW_UT_END macros.
	(DW_CIE_VERSION): Removed.
	(get_DW_UT_name): New function declaration.

libiberty/ChangeLog:

	* dwarfnames.c (get_DW_UT_name): Define using DW_UT_FIRST, DW_UT
	and DW_UT_END.