GNU Tools Weekly News Week 57 (September 27, 2026)

[GNU Tools weekly via Gdb <gdb@sourceware.org>]

GNU Tools Weekly News Week 57 (September 27, 2026)
Note there will be no newsletter next week due to the cauldron.

Release updates for GNU toolchain:
 * GDB 18.1.0 was released
  * https://inbox.sourceware.org/gdb/announce.6ab698d7.84bf0792.34ed8d.a212@mx.google.com/

GNU toolchain conference reminders:
 *  GNU Tools Cauldron 2026
  * This Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news (including sourceware news):
 *

GCC easy issue to tackle of the week:
 *  Missed optimization in math expression: optimize float / in some cases
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83715
  * Hint, this is like previous one: https://gcc.gnu.org/PR126745;
though slightly more involved due to float rules
  *  Reach out to Andrea Pinski <andrew.pinski@oss.qualcomm.com> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-4503 ... r17-4705 -  203 commits
 * match: Fold redundant integer-float-integer conversions
  * https://gcc.gnu.org/r17-4503-gd0e28326d4254e
 * match: fold extract-bitfield-and-shift expressions
  * https://gcc.gnu.org/r17-4511-g885ad73e630ca2
 * aarch64: Improve isnan, isfinite, isinf and isnormal and fpclassify
  * https://gcc.gnu.org/r17-4523-ge8fb8ba77cf7a1
  * https://gcc.gnu.org/r17-4524-g52330debcdf1fc
  * https://gcc.gnu.org/r17-4525-g5cc9ef64063c45
 * match: fold abs(x) comparisons with x
  * https://gcc.gnu.org/r17-4549-g59c8c4bbac4657
 * Improve libstdc++ rege
  * https://gcc.gnu.org/r17-4552 https://gcc.gnu.org/r17-4553
  * https://gcc.gnu.org/r17-4554 https://gcc.gnu.org/r17-4555
 * AArch64: Turn off outline atomics with -mcmodel=large
  * https://gcc.gnu.org/r17-4655-gee5bf81d7816b0
 * simplify-rtx: [SU]MUL_HIGHPART RTL simplifications
  * https://gcc.gnu.org/r17-4656-gd382f953805cb0
 * C++26 P3769R1: Clarification of placement new deallocation as a DR
  * https://gcc.gnu.org/r17-4658-geed9f52920aa36
 * range-ops: derive operand equality from a zero MINUS_EXPR
  * https://gcc.gnu.org/r17-4663-gbddea69ee406a0
 * match.pd: Fold (a != 0) | (popcount(a) == n) and related patterns
  * https://gcc.gnu.org/r17-4693-g56efa4a739786b
 * vect: Look through promotions for SAT_TRUNC
  * https://gcc.gnu.org/r17-4697-g19378ecd385156
 * middle-end: fold VEC_UNPACK_LO/_HI over poly constants
  * https://gcc.gnu.org/r17-4593-g1743eb860b739c

GCC discussion:
 *
GCC bugzilla stats
 *  123 new issues filed
 *  63 issues closed

binutils/gdb commits:
 * LoongArch: Enable shared library and PIE support for loongarch*-elf
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=196286d25ccc652dc086ae173d1cfa836bed0618
 * RISC-V: Enable shared library and PIE support for riscv*-elf
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=b73d23cccf5568321cabaad3a8ec5cddafdef4ec
 * RISC-V: Add optional register argument to tail pseudo
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=441953ac9d0b2902be92906817c68feadccd190f

gdb discussion:
 *
binutils discussion:
  *
glibc commits:
 * math: Sync lgamma, acosf, exp10m1f, and tgamma with CORE-MATH
  * https://sourceware.org/cgit/glibc/log/?id=90156a65a6318b2e1a5ef44501f50fe87db1b601&qt=range&q=90156a65a6318b2e1a5ef44501f50fe87db1b601...1555d46b08dba3a9abbcd956237108b3072f4290%5E
 * AArch64: Add SVE2 memchr
  * https://sourceware.org/cgit/glibc/commit/?id=3edeb81021feff11a3d0e934d68446f6a67dd1a3
 *
glibc discussion:
 * segfault after reallocation (Was: malloc: Change mmap chunk layout)
  * https://inbox.sourceware.org/libc-alpha/armngyyT1otFqpSq@end/