https://gcc.gnu.org/g:576dd2f7ef0dbc30b460176442e63b08c642676c
commit r16-7255-g576dd2f7ef0dbc30b460176442e63b08c642676c Author: Richard Biener <[email protected]> Date: Tue Feb 3 09:26:01 2026 +0100 ipa/123416 - fix IPA modref summary merging after inlining There's a typo in the condition skipping load collapsing when there's no callee modref summary. We do have to collapse loads for the destination iff the callee performs any loads which includes when the callee is ECF_PURE. The LTO summary part already gets this correct. PR ipa/123416 * ipa-modref.cc (ipa_merge_modref_summary_after_inlining): Fix typo in condtion for load merging when no callee summary. * gcc.dg/torture/pr123416.c: New testcase. Diff: --- gcc/ipa-modref.cc | 2 +- gcc/testsuite/gcc.dg/torture/pr123416.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/gcc/ipa-modref.cc b/gcc/ipa-modref.cc index 372f73543617..fc00acecfce7 100644 --- a/gcc/ipa-modref.cc +++ b/gcc/ipa-modref.cc @@ -5352,7 +5352,7 @@ ipa_merge_modref_summary_after_inlining (cgraph_edge *edge) if (!callee_info && to_info) { - if (!(flags & (ECF_CONST | ECF_PURE | ECF_NOVOPS))) + if (!(flags & (ECF_CONST | ECF_NOVOPS))) to_info->loads->collapse (); if (!ignore_stores) to_info->stores->collapse (); diff --git a/gcc/testsuite/gcc.dg/torture/pr123416.c b/gcc/testsuite/gcc.dg/torture/pr123416.c new file mode 100644 index 000000000000..83a126da4456 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr123416.c @@ -0,0 +1,28 @@ +/* { dg-do run } */ +/* { dg-additional-options "-fno-strict-aliasing" } */ + +struct a { + int b; +} c; + +int d; + +static struct a +g() +{ + int a[2], b, f = 0; + for (; f < 2; f++) + a[f] = 1; + b = a[0]; + if (b) + return c; +} +int main() +{ + c.b = 1; + struct a e = g(); + c = g(); + if (!c.b || !e.b) + __builtin_abort(); + return 0; +}
