https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89889
Bug ID: 89889 Summary: worse code compared to clang with alloca() Product: gcc Version: 9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: john.boyer at tutanota dot com Target Milestone: --- Example: https://godbolt.org/z/MLZAA6. Why is the push/lea/leave necessary? Shouldn't modifying the stack pointer be enough?