On Thu, 9 Jul 2026, Michal Jires wrote:
> Cache partitioning asserts that {min,max}_partition_size parameter
> cannot be 0 to prevent later divisions by zero. This is needlessly
> strict, we can clamp the value to 1 to get reasonable/expected behavior.
Can you instead add IntegerRage(1, 2147483647) to the params in
param.opt?
> PR lto/125257
>
> gcc/lto/ChangeLog:
>
> * lto-partition.cc: Handle min/max_partition_size = 0 for
> cache partitioning.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/lto/pr125257_0.c: New test.
> ---
> gcc/lto/lto-partition.cc | 6 ++----
> gcc/testsuite/gcc.dg/lto/pr125257_0.c | 6 ++++++
> 2 files changed, 8 insertions(+), 4 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/lto/pr125257_0.c
>
> diff --git a/gcc/lto/lto-partition.cc b/gcc/lto/lto-partition.cc
> index 076cb002a11..5033ae3f97d 100644
> --- a/gcc/lto/lto-partition.cc
> +++ b/gcc/lto/lto-partition.cc
> @@ -987,11 +987,9 @@ public:
>
> protected:
> partitioner_base (int64_t min_partition_size, int64_t max_partition_size):
> - min_partition_size (min_partition_size),
> - max_partition_size (max_partition_size)
> + min_partition_size (std::max<int64_t>(min_partition_size, 1)),
> + max_partition_size (std::max<int64_t>(max_partition_size, 1))
> {
> - gcc_assert (min_partition_size != 0);
> - gcc_assert (max_partition_size != 0);
> }
> virtual ~partitioner_base ()
> {}
> diff --git a/gcc/testsuite/gcc.dg/lto/pr125257_0.c
> b/gcc/testsuite/gcc.dg/lto/pr125257_0.c
> new file mode 100644
> index 00000000000..e3821150a18
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/lto/pr125257_0.c
> @@ -0,0 +1,6 @@
> +/* PR lto/125257 */
> +/* { dg-lto-do link } */
> +/* { dg-lto-options { "-O0 -flto --param=lto-min-partition=0
> --param=lto-max-partition=0" } } */
> +
> +int main() {}
> +__attribute__((used)) void foo() {}
>
--
Richard Biener <[email protected]>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Jochen Jaser, Andrew McDonald; (HRB 36809, AG Nuernberg)
