Implement C++14 numeric separators

C++14 allows the use of the apostrophe as a numeric separator; that
is, "23000" and "23'000" represent the same number.  This patch
implements this for gdb's C++ parser and the C++ name canonicalizer.

I did this unconditionally for all C variants because I think it's
unambiguous.

For the name canonicalizer, there's at least one compiler that can
emit constants with this form, see bug 30845.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23457
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30845
Approved-By: John Baldwin <jhb@FreeBSD.org>

diff --git a/gdb/c-exp.y b/gdb/c-exp.y
index 5db63551d218f0c7c2e2c419dcb857724395321c..60223172a23c91899b481aecb46187490b388d88 100644 (file)
--- a/gdb/c-exp.y
+++ b/gdb/c-exp.y
@@ -2755,6 +2755,10 @@ lex_one_token (struct parser_state *par_state, bool *is_quoted_name)
            hex = 0;
          }
 
+       /* If the token includes the C++14 digits separator, we make a
+          copy so that we don't have to handle the separator in
+          parse_number.  */
+       std::optional<std::string> no_tick;
        for (;; ++p)
          {
            /* This test includes !hex because 'e' is a valid hex digit
@@ -2771,18 +2775,32 @@ lex_one_token (struct parser_state *par_state, bool *is_quoted_name)
            else if (((got_e && (p[-1] == 'e' || p[-1] == 'E'))
                      || (got_p && (p[-1] == 'p' || p[-1] == 'P')))
                     && (*p == '-' || *p == '+'))
-             /* This is the sign of the exponent, not the end of the
-                number.  */
-             continue;
+             {
+               /* This is the sign of the exponent, not the end of
+                  the number.  */
+             }
+           else if (*p == '\'')
+             {
+               if (!no_tick.has_value ())
+                 no_tick.emplace (tokstart, p);
+               continue;
+             }
            /* We will take any letters or digits.  parse_number will
               complain if past the radix, or if L or U are not final.  */
            else if ((*p < '0' || *p > '9')
                     && ((*p < 'a' || *p > 'z')
                                  && (*p < 'A' || *p > 'Z')))
              break;
+           if (no_tick.has_value ())
+             no_tick->push_back (*p);
          }
-       toktype = parse_number (par_state, tokstart, p - tokstart,
-                               got_dot | got_e | got_p, &yylval);
+       if (no_tick.has_value ())
+         toktype = parse_number (par_state, no_tick->c_str (),
+                                 no_tick->length (),
+                                 got_dot | got_e | got_p, &yylval);
+       else
+         toktype = parse_number (par_state, tokstart, p - tokstart,
+                                 got_dot | got_e | got_p, &yylval);
        if (toktype == ERROR)
          error (_("Invalid number \"%.*s\"."), (int) (p - tokstart),
                 tokstart);

diff --git a/gdb/cp-name-parser.y b/gdb/cp-name-parser.y
index a84051a1b050fef132626879135560820df848be..c0138efc64df7cb8cb6a75bdef22736bb9fa33c0 100644 (file)
--- a/gdb/cp-name-parser.y
+++ b/gdb/cp-name-parser.y
@@ -1686,6 +1686,10 @@ yylex (YYSTYPE *lvalp, cpname_state *state)
            hex = 0;
          }
 
+       /* If the token includes the C++14 digits separator, we make a
+          copy so that we don't have to handle the separator in
+          parse_number.  */
+       std::optional<std::string> no_tick;
        for (;; ++p)
          {
            /* This test includes !hex because 'e' is a valid hex digit
@@ -1703,16 +1707,31 @@ yylex (YYSTYPE *lvalp, cpname_state *state)
              got_dot = 1;
            else if (got_e && (p[-1] == 'e' || p[-1] == 'E')
                     && (*p == '-' || *p == '+'))
-             /* This is the sign of the exponent, not the end of the
-                number.  */
-             continue;
+             {
+               /* This is the sign of the exponent, not the end of
+                  the number.  */
+             }
+           /* C++14 allows a separator.  */
+           else if (*p == '\'')
+             {
+               if (!no_tick.has_value ())
+                 no_tick.emplace (tokstart, p);
+               continue;
+             }
            /* We will take any letters or digits.  parse_number will
               complain if past the radix, or if L or U are not final.  */
            else if (! ISALNUM (*p))
              break;
+           if (no_tick.has_value ())
+             no_tick->push_back (*p);
          }
-       toktype = state->parse_number (tokstart, p - tokstart, got_dot|got_e,
-                                      lvalp);
+       if (no_tick.has_value ())
+         toktype = state->parse_number (no_tick->c_str (),
+                                        no_tick->length (),
+                                        got_dot|got_e, lvalp);
+       else
+         toktype = state->parse_number (tokstart, p - tokstart,
+                                        got_dot|got_e, lvalp);
        if (toktype == ERROR)
          {
            yyerror (state, _("invalid number"));
@@ -2041,6 +2060,8 @@ canonicalize_tests ()
   should_be_the_same ("x::y::z<0b111>", "x::y::z<7>");
   should_be_the_same ("x::y::z<0b111>", "x::y::z<0t7>");
   should_be_the_same ("x::y::z<0b111>", "x::y::z<0D7>");
+
+  should_be_the_same ("x::y::z<0xff'ff>", "x::y::z<65535>");
 }
 
 #endif

diff --git a/gdb/testsuite/gdb.cp/misc.exp b/gdb/testsuite/gdb.cp/misc.exp
index 264294f857d60ab13665ceb2c873eb264a4d2326..bcb20f85eeea2d3a5d04268bde855d6f003558df 100644 (file)
--- a/gdb/testsuite/gdb.cp/misc.exp
+++ b/gdb/testsuite/gdb.cp/misc.exp
@@ -114,3 +114,7 @@ gdb_test "print *(number_ref + v_bool_array)" "\\$\[0-9\]* = false" \
     "integer reference addition with pointer"
 gdb_test "print *(v_bool_array - number_ref)" "\\$\[0-9\]* = false" \
     "pointer subtraction with integer reference"
+
+# C++14 digit separator.
+gdb_test "print 23'23" " = 2323"
+gdb_test "print 2'3.5" " = 23.5"