On Tue, 16 Sep 2025 21:22:52 +0000 Eliav Farber farbere@amazon.com wrote:
This series backports seven commits from v5.15.y that update minmax.h and related code:
- ed6e37e30826 ("tracing: Define the is_signed_type() macro once")
- 998f03984e25 ("minmax: sanity check constant bounds when clamping")
- d470787b25e6 ("minmax: clamp more efficiently by avoiding extra comparison")
- 1c2ee5bc9f11 ("minmax: fix header inclusions")
- d53b5d862acd ("minmax: allow min()/max()/clamp() if the arguments have the same signedness.")
- 7ed91c5560df ("minmax: allow comparisons of 'int' against 'unsigned char/short'")
- 22f7794ef5a3 ("minmax: relax check to allow comparison between unsigned arguments and signed constants")
I think you need to pick up the later changes (from Linus) as well. Without them nested min() and max() can generate very long lines from the pre-processor (tens of megabytes) that cause very slow and/or failing compilations on 32bit and other memory-limited systems.
There are a few other changes needed at the same time. The current min() and max() can't be used in a few places because they aren't 'constant enough' with constant arguments.
David
The main motivation is commit d53b5d862acd, which removes the strict type check in min()/max() when both arguments have the same signedness. Without this, kernel 5.10 builds can emit warnings that become build failures when -Werror is used.
Additionally, commit ed6e37e30826 from tracing is required as a dependency; without it, compilation fails.
Andy Shevchenko (1): minmax: fix header inclusions
Bart Van Assche (1): tracing: Define the is_signed_type() macro once
David Laight (3): minmax: allow min()/max()/clamp() if the arguments have the same signedness. minmax: allow comparisons of 'int' against 'unsigned char/short' minmax: relax check to allow comparison between unsigned arguments and signed constants
Jason A. Donenfeld (2): minmax: sanity check constant bounds when clamping minmax: clamp more efficiently by avoiding extra comparison
include/linux/compiler.h | 6 +++ include/linux/minmax.h | 89 ++++++++++++++++++++++++++---------- include/linux/overflow.h | 1 - include/linux/trace_events.h | 2 - 4 files changed, 70 insertions(+), 28 deletions(-)