https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126066
Bug ID: 126066
Summary: ice in lvalue_kind, at cp/tree.cc:285 with -Wall
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: dcb314 at hotmail dot com
Target Milestone: ---
Given the following C++ source code, from the llvm clang-tools-extra
testsuite:
void testRequires() {
if constexpr (requires(int &a) { a = 0; }) {
}
}
recent g++ trunk does this:
foundBugs $ ../results/bin/g++ -c bug1226.cc
foundBugs $ ../results/bin/g++ -c -Wall bug1226.cc
bug1226.cc: In function ‘void testRequires()’:
bug1226.cc:4:44: internal compiler error: in lvalue_kind, at cp/tree.cc:285
4 | if constexpr (requires(int &a) { a = 0; }) {
| ^
0x2350717 internal_error
/home/dcb42/gcc/working/gcc/../../trunk/gcc/diagnostic-global-context.cc:787
0x2359f5b fancy_abort
/home/dcb42/gcc/working/gcc/../../trunk/gcc/diagnostics/context.cc:1813
0x7ae67c lvalue_kind
/home/dcb42/gcc/working/gcc/../../trunk/gcc/cp/tree.cc:285
0x7ae9d5 real_lvalue_p
/home/dcb42/gcc/working/gcc/../../trunk/gcc/cp/tree.cc:366
The compiler is:
$ ~/gcc/results/bin/g++ -v
Using built-in specs.
COLLECT_GCC=/home/dcb42/gcc/results/bin/g++
COLLECT_LTO_WRAPPER=/home/dcb42/gcc/results.20260701.ubsan/libexec/gcc/x86_64-pc-linux-gnu/17.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../trunk/configure
--prefix=/home/dcb42/gcc/results.20260701.ubsan --disable-bootstrap
--disable-doc --disable-multilib --with-build-config=bootstrap-ubsan
--with-pkgversion=cc195f7b11a4061f --enable-checking=yes
--enable-languages=c,c++,fortran
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 17.0.0 20260701 (experimental) (cc195f7b11a4061f)
$
The bug first appears sometime before g:564af5667f3e0277
at the start of year 2026.
