https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86842
Bug ID: 86842
Summary: Allow run-time checks of pre- and postconditions
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: fiesh at zefix dot tv
Target Milestone: ---
Preface: A rather hard-to-find set of bugs is that introduced by violating
run-time preconditions imposed by certain functions. For example, failing to
satisfy the Compare requirement for std::sort can lead to tricky problems
ranging from segmentation faults to programs just running fine and sometimes
doing something not quite expected.
It would be great if there was a means to activate run-time assertions on these
preconditions, as well as on postconditions. In terms of
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0788r3.pdf ,
everything listed as "Expects:" and "Ensures:" could be checked by a run-time
check.
Since in general checking a sentence with n universal quantifiers will result
in O(N^n) many operations, it might be meaningful to separate those by
different macros, allowing the user control over the amount of complexity
degradation they allow for their debug build. In addition, checks whose
complexity is within the algorithm's complexity class already might be enabled
in Debug Mode Lite by default.
(This extends https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60519 )
