[Bug target/119953] [15/16 Regression] Compiling libstdc++ on MSP430 fails

2025-08-08 Thread rguenth at gcc dot gnu.org via Gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119953

Richard Biener  changed:

   What|Removed |Added

   Target Milestone|15.2|15.3

--- Comment #9 from Richard Biener  ---
GCC 15.2 is being released, retargeting bugs to 15.3.

[Bug target/119953] [15/16 Regression] Compiling libstdc++ on MSP430 fails

2025-06-05 Thread redi at gcc dot gnu.org via Gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119953

Jonathan Wakely  changed:

   What|Removed |Added

 CC||law at gcc dot gnu.org
   Target Milestone|--- |15.2
Summary|Compiling libstdc++ on  |[15/16 Regression]
   |MSP430 fails|Compiling libstdc++ on
   ||MSP430 fails
  Known to fail||15.1.0
  Known to work||14.1.0

--- Comment #8 from Jonathan Wakely  ---
Seems to have regressed with r15-2196-g88d16194d0c8a6

Author: Jeff Law
Date:   Mon Jul 22 08:45:10 2024 -0600

[NFC][PR rtl-optimization/115877] Avoid setting irrelevant bit groups as
live in ext-dce

Another patch to refine liveness computations.  This should be NFC and is
designed to help debugging.

In simplest terms the patch avoids setting bit groups outside the size of a
pseudo as live.  Consider a HImode pseudo, bits 16..63 for such a pseudo
don't
really have meaning, yet we often set bit groups related to bits 16.63 on
in
the liveness bitmaps.

This makes debugging harder than it needs to be by simply having larger
bitmaps
to verify when walking through the code in a debugger.

This has been bootstrapped and regression tested on x86_64.  It's also been
tested on the crosses in my tester without regressions.

Pushing to the trunk,

PR rtl-optimization/115877
gcc/
* ext-dce.cc (group_limit): New function.
(mark_reg_live): Likewise.
(ext_dce_process_sets): Use new functions.
(ext_dce_process_uses): Likewise.
(ext_dce_init): Likewise.