Ping.
On Fri, Jul 14, 2017 at 03:38:05PM +0200, Marek Polacek wrote:
> I think David might be able to approve this one, so CCing.
>
> On Tue, Jul 11, 2017 at 03:23:16PM +0200, Marek Polacek wrote:
> > This patch fixes a bogus -Wmultistatement-macros warning. The code didn't
> > notice that what came after a guard such as else was actually wrapped in { }
> > which is a correct use. This bogus warning only triggered when the body of
> > a conditional was coming from a different expansion than the conditional
> > itself.
> >
> > Bootstrapped/regtested on x86_64-linux, ok for trunk?
> >
> > 2017-07-11 Marek Polacek <pola...@redhat.com>
> >
> > PR c/81364
> > * c-parser.c (c_parser_else_body): Don't warn about multistatement
> > macro expansion if the body is in { }.
> > (c_parser_while_statement): Likewise.
> > (c_parser_for_statement): Likewise.
> >
> > * Wmultistatement-macros-12.c: New test.
> >
> > diff --git gcc/c/c-parser.c gcc/c/c-parser.c
> > index f8fbc92..7524a73 100644
> > --- gcc/c/c-parser.c
> > +++ gcc/c/c-parser.c
> > @@ -5557,7 +5557,8 @@ c_parser_else_body (c_parser *parser, const
> > token_indent_info &else_tinfo,
> > }
> > else
> > {
> > - body_loc_after_labels = c_parser_peek_token (parser)->location;
> > + if (!c_parser_next_token_is (parser, CPP_OPEN_BRACE))
> > + body_loc_after_labels = c_parser_peek_token (parser)->location;
> > c_parser_statement_after_labels (parser, NULL, chain);
> > }
> >
> > @@ -5811,6 +5812,7 @@ c_parser_while_statement (c_parser *parser, bool
> > ivdep, bool *if_p)
> > = get_token_indent_info (c_parser_peek_token (parser));
> >
> > location_t loc_after_labels;
> > + bool open_brace = c_parser_next_token_is (parser, CPP_OPEN_BRACE);
> > body = c_parser_c99_block_statement (parser, if_p, &loc_after_labels);
> > c_finish_loop (loc, cond, NULL, body, c_break_label, c_cont_label, true);
> > add_stmt (c_end_compound_stmt (loc, block, flag_isoc99));
> > @@ -5820,7 +5822,7 @@ c_parser_while_statement (c_parser *parser, bool
> > ivdep, bool *if_p)
> > = get_token_indent_info (c_parser_peek_token (parser));
> > warn_for_misleading_indentation (while_tinfo, body_tinfo, next_tinfo);
> >
> > - if (next_tinfo.type != CPP_SEMICOLON)
> > + if (next_tinfo.type != CPP_SEMICOLON && !open_brace)
> > warn_for_multistatement_macros (loc_after_labels, next_tinfo.location,
> > while_tinfo.location, RID_WHILE);
> >
> > @@ -6109,6 +6111,7 @@ c_parser_for_statement (c_parser *parser, bool ivdep,
> > bool *if_p)
> > = get_token_indent_info (c_parser_peek_token (parser));
> >
> > location_t loc_after_labels;
> > + bool open_brace = c_parser_next_token_is (parser, CPP_OPEN_BRACE);
> > body = c_parser_c99_block_statement (parser, if_p, &loc_after_labels);
> >
> > if (is_foreach_statement)
> > @@ -6122,7 +6125,7 @@ c_parser_for_statement (c_parser *parser, bool ivdep,
> > bool *if_p)
> > = get_token_indent_info (c_parser_peek_token (parser));
> > warn_for_misleading_indentation (for_tinfo, body_tinfo, next_tinfo);
> >
> > - if (next_tinfo.type != CPP_SEMICOLON)
> > + if (next_tinfo.type != CPP_SEMICOLON && !open_brace)
> > warn_for_multistatement_macros (loc_after_labels, next_tinfo.location,
> > for_tinfo.location, RID_FOR);
> >
> > diff --git gcc/testsuite/c-c++-common/Wmultistatement-macros-12.c
> > gcc/testsuite/c-c++-common/Wmultistatement-macros-12.c
> > index e69de29..ac8915c 100644
> > --- gcc/testsuite/c-c++-common/Wmultistatement-macros-12.c
> > +++ gcc/testsuite/c-c++-common/Wmultistatement-macros-12.c
> > @@ -0,0 +1,43 @@
> > +/* PR c/81364 */
> > +/* { dg-do compile } */
> > +/* { dg-options "-Wmultistatement-macros" } */
> > +
> > +#define FOO0 if (1) { } else
> > +#define TST0 \
> > +void bar0 (void) \
> > +{ \
> > + FOO0 { } /* { dg-bogus "macro expands to multiple statements" } */ \
> > +}
> > +TST0
> > +
> > +#define FOO1 for (;;)
> > +#define TST1 \
> > +void bar1 (void) \
> > +{ \
> > + FOO1 { } /* { dg-bogus "macro expands to multiple statements" } */ \
> > +}
> > +TST1
> > +
> > +#define FOO2 while (1)
> > +#define TST2 \
> > +void bar2 (void) \
> > +{ \
> > + FOO2 { } /* { dg-bogus "macro expands to multiple statements" } */ \
> > +}
> > +TST2
> > +
> > +#define FOO3 switch (1)
> > +#define TST3 \
> > +void bar3 (void) \
> > +{ \
> > + FOO3 { } /* { dg-bogus "macro expands to multiple statements" } */ \
> > +}
> > +TST3
> > +
> > +#define FOO4 if (1)
> > +#define TST4 \
> > +void bar4 (void) \
> > +{ \
> > + FOO4 { } /* { dg-bogus "macro expands to multiple statements" } */ \
> > +}
> > +TST4
> >
> > Marek
>
> Marek
Marek
