Add -fdiagnostics-format={json-stderr|json-file}

This commit adds -fdiagnostics-format=json-file, writing to
DUMP_BASE_NAME.gcc.json, and adds -fdiagnostics-format=json-stderr,
a synonym for the existing -fdiagnostics-format=json.

gcc/ChangeLog:
	* common.opt (fdiagnostics-format=): Add json-stderr and json-file
	to description.
	(DIAGNOSTICS_OUTPUT_FORMAT_JSON): Rename to...
	(DIAGNOSTICS_OUTPUT_FORMAT_JSON_STDERR): ...this.
	(diagnostics_output_format): Add json-stderr and json-file.
	* diagnostic-format-json.cc (json_flush_to_file): New.
	(json_final_cb): Convert to...
	(json_flush_to_file): ...this, ...
	(json_stderr_final_cb): ...this, and...
	(json_file_final_cb): ...this.
	(diagnostic_output_format_init): Move to diagnostic.cc.
	(json_output_base_file_name): New.
	(diagnostic_output_format_init_json): New.
	(diagnostic_output_format_init_json_stderr): New.
	(diagnostic_output_format_init_json_file): New.
	* diagnostic.cc (diagnostic_output_format_init): Move here from
	diagnostic-format-json.cc; update for changes to enum.
	* diagnostic.h (enum diagnostics_output_format): Rename
	DIAGNOSTICS_OUTPUT_FORMAT_JSON to
	DIAGNOSTICS_OUTPUT_FORMAT_JSON_STDERR, and add
	DIAGNOSTICS_OUTPUT_FORMAT_JSON_FILE.
	(diagnostic_output_format_init): Add base_file_name param.
	(diagnostic_output_format_init_json_stderr): New decl.
	(diagnostic_output_format_init_json_file): New dec.
	* doc/invoke.texi (-fdiagnostics-format=): Add "json-stderr" and
	"json-file".  Rewrite so that the existing "json" is a synonym of
	"json-stderr".
	* gcc.cc (driver_handle_option): Pass dump_base_name to
	diagnostic_output_format_init.
	* opts.cc (common_handle_option): Likewise.

gcc/testsuite/ChangeLog:
	* c-c++-common/diagnostic-format-json-file-1.c: New test.
	* c-c++-common/diagnostic-format-json-stderr-1.c: New test.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>

1 files changed, 11 insertions, 6 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 71098d8..d85b66f 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -301,7 +301,7 @@ Objective-C and Objective-C++ Dialects}.
 -fdiagnostics-show-location=@r{[}once@r{|}every-line@r{]}  @gol
 -fdiagnostics-color=@r{[}auto@r{|}never@r{|}always@r{]}  @gol
 -fdiagnostics-urls=@r{[}auto@r{|}never@r{|}always@r{]}  @gol
--fdiagnostics-format=@r{[}text@r{|}json@r{]}  @gol
+-fdiagnostics-format=@r{[}text@r{|}json@r{|}json-stderr@r{|}json-file@r{]}  @gol
 -fno-diagnostics-show-option  -fno-diagnostics-show-caret @gol
 -fno-diagnostics-show-labels  -fno-diagnostics-show-line-numbers @gol
 -fno-diagnostics-show-cwe  @gol
@@ -5305,14 +5305,19 @@ Unicode characters.  For the example above, the following will be printed:
 @item -fdiagnostics-format=@var{FORMAT}
 @opindex fdiagnostics-format
 Select a different format for printing diagnostics.
-@var{FORMAT} is @samp{text} or @samp{json}.
+@var{FORMAT} is @samp{text}, @samp{json}, @samp{json-stderr},
+or @samp{json-file}.
+
 The default is @samp{text}.
 
-The @samp{json} format consists of a top-level JSON array containing JSON
-objects representing the diagnostics.
+The @samp{json} format is a synonym for @samp{json-stderr}.
+The @samp{json-stderr} and @samp{json-file} formats are identical, apart from
+where the JSON is emitted to - with the former, the JSON is emitted to stderr,
+whereas with @samp{json-file} it is written to @file{@var{source}.gcc.json}.
 
-The JSON is emitted as one line, without formatting; the examples below
-have been formatted for clarity.
+The emitted JSON consists of a top-level JSON array containing JSON objects
+representing the diagnostics.  The JSON is emitted as one line, without
+formatting; the examples below have been formatted for clarity.
 
 Diagnostics can have child diagnostics.  For example, this error and note: