https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102088
--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
The patch below changes the latest warning to the following without any dg.exp
test failures:
z.c: In function ‘f’:
z.c:9:3: warning: ‘x’ may be used uninitialized [-Wmaybe-uninitialized]
9 | return z;
| ^~~~~~~~
z.c:3:7: note: declared here, initialized if ‘i == 0’
3 | int x, y = j, z;
| ^
diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index 356cf2504d4..73c303b1b4f 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -6168,6 +6168,12 @@ c_parser_statement_after_labels (c_parser *parser, bool
*if_p,
mark_exp_read (expr.value);
stmt = c_finish_return (EXPR_LOC_OR_LOC (expr.value, xloc),
expr.value, expr.original_type);
+ if (stmt)
+ {
+ /* Set the statement location to include the operand. */
+ xloc = make_location (loc, loc, xloc);
+ SET_EXPR_LOCATION (stmt, xloc);
+ }
goto expect_semicolon;
}
break;
Though ideally, the warning would point to the uninitialized read, like so:
z.c: In function ‘f’:
z.c:9:3: warning: ‘x’ may be used uninitialized [-Wmaybe-uninitialized]
5 | z = x;
| ^
But that's not in the IL at -O2 when the warning runs.
