https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99527
Bug ID: 99527 Summary: ICE when using nested lambdas Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: janekb04 at icloud dot com Target Milestone: --- Created attachment 50355 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50355&action=edit The code that causes the error, the preprocessed version of the code and the compiler output When the code in the attachment is compiled it causes an Internal Compiler Error. The code is also available on godbolt: https://godbolt.org/z/vn35js . The code doesn't emit any warning using -Wall -Wextra -Wpedantic. -fno-strict-aliasing -fwrapv don't seem to have any effect. All the information about the compiler version and environment is available on godbolt. For clarity, here is the version and flags. version: g++ (Compiler-Explorer-Build) 11.0.1 20210309 (experimental) Copyright (C) 2021 Free Software Foundation, Inc. flags: -std=c++20 The code that causes the error, the preprocessed version of the code and the compiler output are in the attachment. Not sure if it is relevant, but I will say just in case that the code is based on a technique I discussed here: https://janbielak.com/index.php/2021/01/15/anonymous-types-in-c/ .