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| author | Martin Uecker <uecker@tugraz.at> | 2023-08-04 07:48:21 +0200 |
|---|---|---|
| committer | Martin Uecker <uecker@tugraz.at> | 2023-08-05 10:39:44 +0200 |
| commit | 54be338589ea93ad4ff53d22adde476a0582537b (patch) | |
| tree | f5a1196872a60798598f8460e1af6acac5daa2a6 | |
| parent | 5b42ee2cded7c2173ea0e9f9e08dd1d9b226ed3e (diff) | |
| download | gcc-54be338589ea93ad4ff53d22adde476a0582537b.zip gcc-54be338589ea93ad4ff53d22adde476a0582537b.tar.gz gcc-54be338589ea93ad4ff53d22adde476a0582537b.tar.bz2 | |
c: _Generic should not warn in non-active branches [PR68193,PR97100,PR110703]
To avoid false diagnostics, use c_inhibit_evaluation_warnings when
a generic association is known to not match during parsing. We may
still generate false positives if the default branch comes earler than
a specific association that matches.
PR c/68193
PR c/97100
PR c/110703
gcc/c/:
* c-parser.cc (c_parser_generic_selection): Inhibit evaluation
warnings branches that are known not be taken during parsing.
gcc/testsuite/ChangeLog:
* gcc.dg/pr68193.c: New test.
| -rw-r--r-- | gcc/c/c-parser.cc | 12 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr68193.c | 15 |
2 files changed, 26 insertions, 1 deletions
diff --git a/gcc/c/c-parser.cc b/gcc/c/c-parser.cc index 7a9fdda..57a01dc 100644 --- a/gcc/c/c-parser.cc +++ b/gcc/c/c-parser.cc @@ -9392,7 +9392,17 @@ c_parser_generic_selection (c_parser *parser) return error_expr; } + bool match = assoc.type == NULL_TREE + || comptypes (assoc.type, selector_type); + + if (!match) + c_inhibit_evaluation_warnings++; + assoc.expression = c_parser_expr_no_commas (parser, NULL); + + if (!match) + c_inhibit_evaluation_warnings--; + if (assoc.expression.value == error_mark_node) { c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL); @@ -9429,7 +9439,7 @@ c_parser_generic_selection (c_parser *parser) match_found = associations.length (); } } - else if (comptypes (assoc.type, selector_type)) + else if (match) { if (match_found < 0 || matched_assoc.type == NULL_TREE) { diff --git a/gcc/testsuite/gcc.dg/pr68193.c b/gcc/testsuite/gcc.dg/pr68193.c new file mode 100644 index 0000000..2267593 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr68193.c @@ -0,0 +1,15 @@ +/* pr69193 */ +/* { dg-do compile } */ +/* { dg-options "-Wall" } */ + +int +main (void) +{ + int i = 0; + int j = _Generic (i, + int: 0, + long int: (i = (long int) 9223372036854775808UL)); + return i + j; +} + + |