https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81749
Bug ID: 81749 Summary: std::align: runtime error: negation of 8 cannot be represented in type 'size_t' Product: gcc Version: 7.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: max at maxbruckner dot de Target Milestone: --- Created attachment 41944 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41944&action=edit C++ file to reproduce the error When compiling code with clangs undefined behavior sanitizer (clang++ 4.0.1 -fsanitize=unsigned-integer-overflow) that uses std::align, a runtime error occurs: /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/7.1.1/../../../../include/c++/7.1.1/memory:117:54: runtime error: negation of 8 cannot be represented in type 'size_t' (aka 'unsigned long') The issue can be reproduced with the C++ and Makefile from the attachments. The full output of my test: alignof(intmax_t) = 8 alloced = 0x5606f17e7c21 /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/7.1.1/../../../../include/c++/7.1.1/memory:117:54: runtime error: negation of 8 cannot be represented in type 'size_t' (aka 'unsigned long') address = 0x5606f17e7c28 space = 92