From: Tom Tromey Date: Mon, 18 Sep 2017 02:36:41 +0000 (-0600) Subject: Add support for __VA_OPT__ X-Git-Tag: users/ARM/embedded-binutils-master-2017q4~921 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a9bbfbd85fddfea2db30810c33c4bb130a2ef773;p=external%2Fbinutils.git Add support for __VA_OPT__ C++2a adds a "__VA_OPT__" feature that can be used to control the pesky "," emission when the final (variable) argument of a variadic macro is empty. This patch implements this feature for gdb. (A patch to implement it for gcc is pending.) gdb/ChangeLog 2017-09-27 Tom Tromey * macroexp.c (get_next_token_for_substitution): New function. (substitute_args): Call it. Check for __VA_OPT__. gdb/testsuite/ChangeLog 2017-09-27 Tom Tromey * gdb.base/macscp.exp: Add __VA_OPT__ tests. --- diff --git a/gdb/ChangeLog b/gdb/ChangeLog index efe90f0..a12eebe 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2017-09-27 Tom Tromey + + * macroexp.c (get_next_token_for_substitution): New function. + (substitute_args): Call it. Check for __VA_OPT__. + 2017-09-26 Walfred Tedeschi Pedro Alves diff --git a/gdb/macroexp.c b/gdb/macroexp.c index e7a0dad..8d1876e 100644 --- a/gdb/macroexp.c +++ b/gdb/macroexp.c @@ -946,6 +946,30 @@ find_parameter (const struct macro_buffer *tok, return -1; } +/* Helper function for substitute_args that gets the next token and + updates the passed-in state variables. */ + +static void +get_next_token_for_substitution (struct macro_buffer *replacement_list, + struct macro_buffer *token, + char **start, + struct macro_buffer *lookahead, + char **lookahead_start, + int *lookahead_valid, + bool *keep_going) +{ + if (!*lookahead_valid) + *keep_going = false; + else + { + *keep_going = true; + *token = *lookahead; + *start = *lookahead_start; + *lookahead_start = replacement_list->text; + *lookahead_valid = get_token (lookahead, replacement_list); + } +} + /* Given the macro definition DEF, being invoked with the actual arguments given by ARGC and ARGV, substitute the arguments into the replacement list, and store the result in DEST. @@ -996,8 +1020,64 @@ substitute_args (struct macro_buffer *dest, lookahead_rl_start = replacement_list.text; lookahead_valid = get_token (&lookahead, &replacement_list); - for (;;) + /* __VA_OPT__ state variable. The states are: + 0 - nothing happening + 1 - saw __VA_OPT__ + >= 2 in __VA_OPT__, the value encodes the parenthesis depth. */ + unsigned vaopt_state = 0; + + for (bool keep_going = true; + keep_going; + get_next_token_for_substitution (&replacement_list, + &tok, + &original_rl_start, + &lookahead, + &lookahead_rl_start, + &lookahead_valid, + &keep_going)) { + bool token_is_vaopt = (tok.len == 10 + && strncmp (tok.text, "__VA_OPT__", 10) == 0); + + if (vaopt_state > 0) + { + if (token_is_vaopt) + error (_("__VA_OPT__ cannot appear inside __VA_OPT__")); + else if (tok.len == 1 && tok.text[0] == '(') + { + ++vaopt_state; + /* We just entered __VA_OPT__, so don't emit this + token. */ + continue; + } + else if (vaopt_state == 1) + error (_("__VA_OPT__ must be followed by an open parenthesis")); + else if (tok.len == 1 && tok.text[0] == ')') + { + --vaopt_state; + if (vaopt_state == 1) + { + /* Done with __VA_OPT__. */ + vaopt_state = 0; + /* Don't emit. */ + continue; + } + } + + /* If __VA_ARGS__ is empty, then drop the contents of + __VA_OPT__. */ + if (argv[argc - 1].len == 0) + continue; + } + else if (token_is_vaopt) + { + if (!is_varargs) + error (_("__VA_OPT__ is only valid in a variadic macro")); + vaopt_state = 1; + /* Don't emit this token. */ + continue; + } + /* Just for aesthetics. If we skipped some whitespace, copy that to DEST. */ if (tok.text > original_rl_start) @@ -1157,16 +1237,10 @@ substitute_args (struct macro_buffer *dest, if (! substituted) append_tokens_without_splicing (dest, &tok); } - - if (! lookahead_valid) - break; - - tok = lookahead; - original_rl_start = lookahead_rl_start; - - lookahead_rl_start = replacement_list.text; - lookahead_valid = get_token (&lookahead, &replacement_list); } + + if (vaopt_state > 0) + error (_("Unterminated __VA_OPT__")); } diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 4b6cb80..4348e76 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2017-09-27 Tom Tromey + + * gdb.base/macscp.exp: Add __VA_OPT__ tests. + 2017-09-26 Thomas Preud'homme Pedro Alves diff --git a/gdb/testsuite/gdb.base/macscp.exp b/gdb/testsuite/gdb.base/macscp.exp index 54b5ab2..c5cd899 100644 --- a/gdb/testsuite/gdb.base/macscp.exp +++ b/gdb/testsuite/gdb.base/macscp.exp @@ -620,6 +620,18 @@ gdb_test_no_output "macro define va_gnu(args...) varfunc (fixedarg, args)" \ gdb_test_no_output "macro define va2_gnu(args...) varfunc (fixedarg, ## args)" \ "define fourth varargs helper" +gdb_test_no_output \ + "macro define va3_cxx2a(x, ...) varfunc (x __VA_OPT__(,) __VA_ARGS__)" \ + "define fifth varargs helper" + +gdb_test_no_output \ + "macro define va4_cxx2a(x, ...) varfunc (x __VA_OPT__(, __VA_ARGS__))" \ + "define sixth varargs helper" + +gdb_test_no_output \ + "macro define va5_cxx2a(x, ...) varfunc (x __VA_OPT__(,) __VA_OPT__(__VA_ARGS__))" \ + "define seventh varargs helper" + gdb_test "macro expand va_c99(one, two, three)" \ "expands to: *varfunc \\(fixedarg, *one, two, three\\)" \ "c99 varargs expansion" @@ -644,6 +656,58 @@ gdb_test "macro expand va2_gnu()" \ "expands to: *varfunc \\(fixedarg\\)" \ "gnu varargs expansion special splicing without an argument" +gdb_test "macro expand va3_cxx2a(23)" \ + "expands to: *varfunc \\(23 \\)" \ + "C++2a __VA_OPT__ handling without variable argument" + +gdb_test "macro expand va3_cxx2a(23, 24, 25)" \ + "expands to: *varfunc \\(23, 24, 25\\)" \ + "C++2a __VA_OPT__ handling with variable argument" + +gdb_test "macro expand va4_cxx2a(23, 24, 25)" \ + "expands to: *varfunc \\(23, 24, 25\\)" \ + "C++2a __VA_OPT__ conditional __VA_ARGS__ handling with variable argument" + +gdb_test "macro expand va4_cxx2a(23)" \ + "expands to: *varfunc \\(23\\)" \ + "C++2a __VA_OPT__ conditional __VA_ARGS__ handling without variable argument" + +gdb_test "macro expand va5_cxx2a(23, 24, 25)" \ + "expands to: *varfunc \\(23,24, 25\\)" \ + "C++2a double __VA_OPT__ conditional __VA_ARGS__ handling with variable argument" + +gdb_test "macro expand va5_cxx2a(23)" \ + "expands to: *varfunc \\(23\\)" \ + "C++2a double __VA_OPT__ conditional __VA_ARGS__ handling without variable argument" + +gdb_test_no_output \ + "macro define badopt1(x, ...) __VA_OPT__) x" \ + "define first invalid varargs helper" +gdb_test "macro expand badopt1(5)" \ + "__VA_OPT__ must be followed by an open parenthesis" \ + "__VA_OPT__ without open paren" + +gdb_test_no_output \ + "macro define badopt2(x, ...) __VA_OPT__(__VA_OPT__(,)) x" \ + "define second invalid varargs helper" +gdb_test "macro expand badopt2(5)" \ + "__VA_OPT__ cannot appear inside __VA_OPT__" \ + "__VA_OPT__ inside __VA_OPT__" + +gdb_test_no_output \ + "macro define badopt3(x) __VA_OPT__" \ + "define third invalid varargs helper" +gdb_test "macro expand badopt3(5)" \ + "__VA_OPT__ is only valid in a variadic macro" \ + "__VA_OPT__ not in variadic macro" + +gdb_test_no_output \ + "macro define badopt4(x, ...) __VA_OPT__(x" \ + "define fourth invalid varargs helper" +gdb_test "macro expand badopt4(5)" \ + "Unterminated __VA_OPT__" \ + "__VA_OPT__ without closing paren" + # Stringification tests. gdb_test_no_output "macro define str(x) #x" \