Since r223098 ("Implement -Wmisleading-indentation") the backward-jump
generated for a C while- or for-loop can get the wrong line number.
This is because the check for misleading indentation peeks ahead one
token, advancing input_location to after the loop, and then
c_finish_loop() creates the back-jump and calls add_stmt(), which
assigns input_location to the statement by default.
This patch swaps the check for misleading indentation with the finishing
of the loop, such that input_location still has the right value at the
time of any invocations of add_stmt(). Note that this does not fully
cover all cases where the back-jump gets the wrong location.
gcc/c/ChangeLog:
PR debug/67192
* c-parser.c (c_parser_while_statement): Finish the loop before
parsing ahead for misleading indentation.
(c_parser_for_statement): Likewise.
gcc/testsuite/ChangeLog:
PR debug/67192
* gcc.dg/guality/pr67192.c: New test.
---
gcc/c/c-parser.c | 13 +++++----
gcc/testsuite/gcc.dg/guality/pr67192.c | 53 ++++++++++++++++++++++++++++++++++
2 files changed, 60 insertions(+), 6 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/guality/pr67192.c
diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index ec88c65..0c5e4e9 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -5435,13 +5435,13 @@ c_parser_while_statement (c_parser *parser, bool ivdep)
= get_token_indent_info (c_parser_peek_token (parser));
body = c_parser_c99_block_statement (parser);
+ c_finish_loop (loc, cond, NULL, body, c_break_label, c_cont_label, true);
+ add_stmt (c_end_compound_stmt (loc, block, flag_isoc99));
token_indent_info next_tinfo
= get_token_indent_info (c_parser_peek_token (parser));
warn_for_misleading_indentation (while_tinfo, body_tinfo, next_tinfo);
- c_finish_loop (loc, cond, NULL, body, c_break_label, c_cont_label, true);
- add_stmt (c_end_compound_stmt (loc, block, flag_isoc99));
c_break_label = save_break;
c_cont_label = save_cont;
}
@@ -5725,15 +5725,16 @@ c_parser_for_statement (c_parser *parser, bool ivdep)
body = c_parser_c99_block_statement (parser);
- token_indent_info next_tinfo
- = get_token_indent_info (c_parser_peek_token (parser));
- warn_for_misleading_indentation (for_tinfo, body_tinfo, next_tinfo);
-
if (is_foreach_statement)
objc_finish_foreach_loop (loc, object_expression, collection_expression,
body, c_break_label, c_cont_label);
else
c_finish_loop (loc, cond, incr, body, c_break_label, c_cont_label, true);
add_stmt (c_end_compound_stmt (loc, block, flag_isoc99 || c_dialect_objc
()));
+
+ token_indent_info next_tinfo
+ = get_token_indent_info (c_parser_peek_token (parser));
+ warn_for_misleading_indentation (for_tinfo, body_tinfo, next_tinfo);
+
c_break_label = save_break;
c_cont_label = save_cont;
}
diff --git a/gcc/testsuite/gcc.dg/guality/pr67192.c
b/gcc/testsuite/gcc.dg/guality/pr67192.c
new file mode 100644
index 0000000..f6382ef
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/guality/pr67192.c
@@ -0,0 +1,53 @@
+/* PR debug/67192 */
+/* { dg-do run } */
+/* { dg-options "-g -Wmisleading-indentation" } */
+
+volatile int cnt = 0;
+
+__attribute__((noinline, noclone)) static int
+last (void)
+{
+ return ++cnt % 5 == 0;
+}
+
+__attribute__((noinline, noclone)) static void
+do_it (void)
+{
+ asm volatile ("" : : "r" (&cnt) : "memory");
+}
+
+__attribute__((noinline, noclone)) static void
+f1 (void)
+{
+ for (;; do_it())
+ {
+ if (last ())
+ break;
+ }
+ do_it (); /* { dg-final { gdb-test 27 "cnt" "5" } } */
+}
+
+__attribute__((noinline, noclone)) static void
+f2 (void)
+{
+ while (1)
+ {
+ if (last ())
+ break;
+ do_it ();
+ }
+ do_it (); /* { dg-final { gdb-test 39 "cnt" "10" } } */
+}
+
+void (*volatile fnp1) (void) = f1;
+void (*volatile fnp2) (void) = f2;
+
+int
+main ()
+{
+ asm volatile ("" : : "r" (&fnp1) : "memory");
+ asm volatile ("" : : "r" (&fnp2) : "memory");
+ fnp1 ();
+ fnp2 ();
+ return 0;
+}
--
2.3.0
