After spending some time to try retaining some abnormal SSA name
uninitialized uses I gave up and just punt like below.
Bootstrap / regtest running on x86_64-unknown-linux-gnu.
Richard.
2013-05-24 Richard Biener <rguent...@suse.de>
PR tree-optimization/57287
* tree-ssa-uninit.c (compute_uninit_opnds_pos): Disregard
all SSA names that occur in abnormal PHIs.
* gcc.dg/pr57287.c: New testcase.
Index: gcc/tree-ssa-uninit.c
===================================================================
--- gcc/tree-ssa-uninit.c (revision 199284)
+++ gcc/tree-ssa-uninit.c (working copy)
@@ -165,17 +165,12 @@ compute_uninit_opnds_pos (gimple phi)
&& uninit_undefined_value_p (op)
&& !can_skip_redundant_opnd (op, phi))
{
- /* Ignore SSA_NAMEs on abnormal edges to setjmp
- or nonlocal goto receiver. */
if (cfun->has_nonlocal_label || cfun->calls_setjmp)
{
- edge e = gimple_phi_arg_edge (phi, i);
- if (e->flags & EDGE_ABNORMAL)
- {
- gimple last = last_stmt (e->src);
- if (last && stmt_can_make_abnormal_goto (last))
- continue;
- }
+ /* Ignore SSA_NAMEs that appear on abnormal edges
+ somewhere. */
+ if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op))
+ continue;
}
MASK_SET_BIT (uninit_opnds, i);
}
Index: gcc/testsuite/gcc.dg/pr57287.c
===================================================================
--- gcc/testsuite/gcc.dg/pr57287.c (revision 0)
+++ gcc/testsuite/gcc.dg/pr57287.c (working copy)
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wall" } */
+
+#include <setjmp.h>
+
+jmp_buf buf;
+
+void foo (int);
+void bar (int) __attribute__((leaf));
+
+void enumerate_locals (int indent)
+{
+ foo (0);
+ while (indent--)
+ {
+ int local_indent = 8 + (8 * indent);
+ if (local_indent != 8)
+ {
+ setjmp (buf);
+ bar (local_indent); /* { dg-bogus "may be used uninitialized" "" } */
+ }
+ }
+ foo (1);
+}
