https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121206
Bug ID: 121206
Summary: [16 regression] Hang in ranger when building
gromacs-2025.2
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: compile-time-hog, memory-hog
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: sjames at gcc dot gnu.org
Target Milestone: ---
Created attachment 61925
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=61925&action=edit
bt.txt
Originally reported downstream in Gentoo by toralf at
https://bugs.gentoo.org/960345.
```
$ g++ -c gmx_bundle.cpp.ii -march=znver3 -O2 # completes in reasonable time
$ g++ -c gmx_bundle.cpp.ii -march=znver3 -O3 # hangs, gobbling memory
```
After running for a few minutes:
```
#0 0x0000555687e53c39 in memcpy (__dest=0x7fff7183a3d0, __src=0x5556a7be9d78,
__len=80) at /usr/include/bits/string_fortified.h:29
#1 wide_int_storage::wide_int_storage (this=<optimized out>, x=...,
this=<optimized out>, x=...) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/wide-int.h:1198
#2 generic_wide_int<wide_int_storage>::generic_wide_int (this=0x7fff7183a3d0)
at /usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/wide-int.h:775
#3 irange::lower_bound (pair=0, this=0x7fff7183aba8) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/value-range.h:1166
#4 irange::union_ (this=<optimized out>, v=...) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/value-range.cc:1791
#5 0x0000555688510648 in value_range::union_ (this=0x7fff7183b120, r=...) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/value-range.h:785
#6 ranger_cache::propagate_cache (this=0x5556a7974780, name=0x7fd1ee84a630) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-cache.cc:1365
#7 0x000055568844a25e in ranger_cache::fill_block_cache (this=0x5556a7974780,
name=<optimized out>, bb=<optimized out>, def_bb=0x7fd1eeaf9600) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-cache.cc:1653
#8 0x000055568841a941 in ranger_cache::block_range (this=<optimized out>,
r=..., bb=0x7fd1ee81d600, name=0x7fd1ee84a630, calc=true) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-cache.cc:1313
#9 ranger_cache::block_range (this=<optimized out>, r=..., bb=<optimized out>,
name=0x7fd1ee84a630, calc=true) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-cache.cc:1281
#10 gimple_ranger::range_on_entry (this=0x5556a7974740, r=...,
bb=0x7fd1ee81d600, name=0x7fd1ee84a630) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range.cc:174
#11 0x000055568835e282 in gimple_ranger::range_of_expr (this=0x5556a7974740,
r=..., expr=0x7fd1ee84a630, stmt=<optimized out>) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range.cc:146
#12 0x0000555688408382 in fur_stmt::get_operand (this=0x7fff7183d0a0, r=...,
expr=0x7fd1ee84a630) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-fold.cc:143
#13 fold_using_range::range_of_range_op (this=this@entry=0x7fff7183d080, r=...,
handler=..., src=...) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-fold.cc:718
#14 0x0000555688badf1a in fold_using_range::fold_stmt(vrange&, gimple*,
fur_source&, tree_node*) [clone .constprop.2] (this=0x7fff7183d080, r=...,
s=0x7fd1ee81dc00, src=..., name=0x7fd1ee821168) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range-fold.cc:649
#15 0x00005556883f3e92 in gimple_ranger::fold_range_internal
(this=0x5556a7974740, r=..., s=<optimized out>, name=<optimized out>) at
/usr/src/debug/sys-devel/gcc-16.0.9999/gcc-16.0.9999/gcc/gimple-range.cc:282
[...]
```
```
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/16/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/configure
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/16
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/16/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/16
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/16/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/16/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/16/include/g++-v16
--disable-silent-rules --disable-dependency-tracking
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/16/python
--enable-libphobos --enable-objc-gc
--enable-languages=c,c++,d,objc,obj-c++,fortran,ada,cobol,m2,rust
--enable-obsolete --enable-secureplt --disable-werror --with-system-zlib
--enable-nls --without-included-gettext --disable-libunwind-exceptions
--enable-checking=yes,extra,rtl --with-bugurl=https://bugs.gentoo.org/
--with-pkgversion='Gentoo Hardened 16.0.9999 p, commit
37758405f27f9ebf31a0e59044da0c0aa9eda679' --with-gcc-major-version-only
--enable-libstdcxx-time --enable-lto --disable-libstdcxx-pch --enable-shared
--enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu
--enable-multilib --with-multilib-list=m32,m64 --disable-fixed-point
--enable-targets=all --enable-offload-defaulted
--enable-offload-targets=nvptx-none --enable-libgomp --disable-libssp
--enable-libada --disable-cet --disable-systemtap --enable-valgrind-annotations
--disable-vtable-verify --disable-libvtv --with-zstd --with-isl
--disable-isl-version-check --enable-default-pie --enable-host-pie
--enable-host-bind-now --enable-default-ssp --disable-fixincludes
--with-gxx-libcxx-include-dir=/usr/include/c++/v1 --enable-linker-build-id
--with-build-config='bootstrap-O3 bootstrap-lto'
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 16.0.0 20250718 (experimental)
f880cfc2a4e9daa69f7bb3e64c584dde705783b0 (Gentoo Hardened 16.0.9999 p, commit
37758405f27f9ebf31a0e59044da0c0aa9eda679)
```
