We crash here because since r11-3302 the C FE uses codes like SWITCH_STMT
in the else branches in the attached test, and inchash::add_expr in
do_warn_duplicated_branches doesn't handle these front-end codes. In
the C++ FE this works because by the time we get to do_warn_duplicated_branches
we've already cp_genericize'd the SWITCH_STMT tree into a SWITCH_EXPR.
The fix is to call do_warn_duplicated_branches_r only after loops and other
structured control constructs have been lowered.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
gcc/c-family/ChangeLog:
PR c/97125
* c-gimplify.c (c_genericize): Only call do_warn_duplicated_branches_r
after loops and other structured control constructs have been lowered.
gcc/testsuite/ChangeLog:
PR c/97125
* c-c++-common/Wduplicated-branches-15.c: New test.
---
gcc/c-family/c-gimplify.c | 8 ++---
.../c-c++-common/Wduplicated-branches-15.c | 32 +++++++++++++++++++
2 files changed, 36 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/c-c++-common/Wduplicated-branches-15.c
diff --git a/gcc/c-family/c-gimplify.c b/gcc/c-family/c-gimplify.c
index 8b326c99d48..d1e391590dd 100644
--- a/gcc/c-family/c-gimplify.c
+++ b/gcc/c-family/c-gimplify.c
@@ -533,10 +533,6 @@ c_genericize (tree fndecl)
&pset);
}
- if (warn_duplicated_branches)
- walk_tree_without_duplicates (&DECL_SAVED_TREE (fndecl),
- do_warn_duplicated_branches_r, NULL);
-
/* Genericize loops and other structured control constructs. The C++
front end has already done this in lang-specific code. */
if (!c_dialect_cxx ())
@@ -550,6 +546,10 @@ c_genericize (tree fndecl)
pop_cfun ();
}
+ if (warn_duplicated_branches)
+ walk_tree_without_duplicates (&DECL_SAVED_TREE (fndecl),
+ do_warn_duplicated_branches_r, NULL);
+
/* Dump the C-specific tree IR. */
dump_orig = get_dump_info (TDI_original, &local_dump_flags);
if (dump_orig)
diff --git a/gcc/testsuite/c-c++-common/Wduplicated-branches-15.c
b/gcc/testsuite/c-c++-common/Wduplicated-branches-15.c
new file mode 100644
index 00000000000..d4943607086
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wduplicated-branches-15.c
@@ -0,0 +1,32 @@
+/* PR c/97125 */
+/* { dg-do compile } */
+/* { dg-options "-Wduplicated-branches" } */
+
+void foo (void);
+
+void
+fn1 (void)
+{
+ if (0)
+ foo ();
+ else
+ switch (0);
+}
+
+void
+fn2 (void)
+{
+ if (0)
+ foo ();
+ else
+ while (0);
+}
+
+void
+fn3 (void)
+{
+ if (0)
+ foo ();
+ else
+ for (;;);
+}
base-commit: 363e7755f227656684c8e284307ceee451503ca4
--
2.26.2
