Add multibyte character warning option to the assembler.

	* as.c (parse_args): Add support for --multibyte-handling.
	* as.h (multibyte_handling): Declare.
	* app.c (scan_for_multibyte_characters): New function.
	(do_scrub_chars): Call the new function if multibyte warning is
	enabled.
	* input-scrub,c (input_scrub_next_buffer): Call the multibyte
	scanning function if multibyte warnings are enabled.
	* symbols.c (struct symbol_flags): Add multibyte_warned bit.
	(symbol_init): Call the multibyte scanning function if multibyte
	symbol warnings are enabled.
	(S_SET_SEGMENT): Likewise.
	* NEWS: Mention the new feature.
	* doc/as.texi: Document the new feature.
	* testsuite/gas/all/multibyte.s: New test source file.
	* testsuite/gas/all/multibyte1.d: New test driver file.
	* testsuite/gas/all/multibyte1.l: New test expected output.
	* testsuite/gas/all/multibyte2.d: New test driver file.
	* testsuite/gas/all/multibyte2.l: New test expected output.
	* testsuite/gas/all/gas.exp: Run the new tests.

1 files changed, 26 insertions, 4 deletions

diff --git a/gas/doc/as.texi b/gas/doc/as.texi
index 9c1924d..b83f50b 100644
--- a/gas/doc/as.texi
+++ b/gas/doc/as.texi
@@ -245,6 +245,7 @@ gcc(1), ld(1), and the Info entries for @file{binutils} and @file{ld}.
  [@b{--sectname-subst}] [@b{--size-check=[error|warning]}]
  [@b{--elf-stt-common=[no|yes]}]
  [@b{--generate-missing-build-notes=[no|yes]}]
+ [@b{--multibyte-handling=[allow|warn|warn-sym-only]}]
  [@b{--target-help}] [@var{target-options}]
  [@b{--}|@var{files} @dots{}]
 @c
@@ -871,6 +872,18 @@ Set the maximum width of an input source line, as displayed in a listing, to
 Set the maximum number of lines printed in a listing for a single line of input
 to @var{number} + 1.
 
+@item --multibyte-handling=allow
+@itemx --multibyte-handling=warn
+@itemx --multibyte-handling=warn-sym-only
+Controls how the assembler handles multibyte characters in the input.  The
+default (which can be restored by using the @option{allow} argument) is to
+allow such characters without complaint.  Using the @option{warn} argument will
+make the assembler generate a warning message whenever any multibyte character
+is encountered.  Using the @option{warn-sym-only} argument will only cause a
+warning to be generated when a symbol is defined with a name that contains
+multibyte characters.  (References to undefined symbols will not generate a
+warning).
+
 @item --no-pad-sections
 Stop the assembler for padding the ends of output sections to the alignment
 of that section.  The default is to pad the sections, but this can waste space
@@ -2966,9 +2979,11 @@ are noted in @ref{Machine Dependencies}.
 @end ifset
 No symbol may begin with a digit.  Case is significant.
 There is no length limit; all characters are significant.  Multibyte characters
-are supported.  Symbols are delimited by characters not in that set, or by the
-beginning of a file (since the source program must end with a newline, the end
-of a file is not a possible symbol delimiter).  @xref{Symbols}.
+are supported, but note that the setting of the
+@option{--multibyte-handling} option might prevent their use.  Symbols
+are delimited by characters not in that set, or by the beginning of a file
+(since the source program must end with a newline, the end of a file is not a
+possible symbol delimiter).  @xref{Symbols}.
 
 Symbol names may also be enclosed in double quote @code{"} characters.  In such
 cases any characters are allowed, except for the NUL character.  If a double
@@ -3858,11 +3873,18 @@ than @code{Foo}.
 Symbol names do not start with a digit.  An exception to this rule is made for
 Local Labels.  See below.
 
-Multibyte characters are supported.  To generate a symbol name containing
+Multibyte characters are supported, but note that the setting of the
+@option{multibyte-handling} option might prevent their use.
+To generate a symbol name containing
 multibyte characters enclose it within double quotes and use escape codes. cf
 @xref{Strings}.  Generating a multibyte symbol name from a label is not
 currently supported.
 
+Since multibyte symbol names are unusual, and could possibly be used
+maliciously, @command{@value{AS}} provides a command line option
+(@option{--multibyte-handling=warn-sym-only}) which can be used to generate a
+warning message whenever a symbol name containing multibyte characters is defined.
+
 Each symbol has exactly one name.  Each name in an assembly language program
 refers to exactly one symbol.  You may use that symbol name any number of times
 in a program.