public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
* [Bug c++/107388] New: GCC should diagnose unsigned to signed conversion with -Wconversion @ 2022-10-24 23:17 nikolasklauser at berlin dot de 2022-10-24 23:20 ` [Bug c++/107388] " mpolacek at gcc dot gnu.org ` (2 more replies) 0 siblings, 3 replies; 4+ messages in thread From: nikolasklauser at berlin dot de @ 2022-10-24 23:17 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107388 Bug ID: 107388 Summary: GCC should diagnose unsigned to signed conversion with -Wconversion Product: gcc Version: 13.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: nikolasklauser at berlin dot de Target Milestone: --- It looks like GCC currently doesn't diagnose a conversion from unsigned int to int, but as I understand it -Wconversion should diagnose any conversion that might change the value. Here is an example: (Godbolt: https://godbolt.org/z/Mr8KvTW66) #include <cstddef> #include <cstdlib> void func(unsigned int size) { [[maybe_unused]] int v = size; // doesn't get diagnosed } ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/107388] GCC should diagnose unsigned to signed conversion with -Wconversion 2022-10-24 23:17 [Bug c++/107388] New: GCC should diagnose unsigned to signed conversion with -Wconversion nikolasklauser at berlin dot de @ 2022-10-24 23:20 ` mpolacek at gcc dot gnu.org 2022-10-24 23:20 ` mpolacek at gcc dot gnu.org 2022-10-25 19:57 ` nikolasklauser at berlin dot de 2 siblings, 0 replies; 4+ messages in thread From: mpolacek at gcc dot gnu.org @ 2022-10-24 23:20 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107388 Marek Polacek <mpolacek at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID CC| |mpolacek at gcc dot gnu.org --- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> --- This is -Wsign-conversion: $ ./cc1plus -quiet t.C -Wsign-conversion t.C: In function ‘void func(unsigned int)’: t.C:2:28: warning: conversion to ‘int’ from ‘unsigned int’ may change the sign of the result [-Wsign-conversion] 2 | [[maybe_unused]] int v = size; // doesn't get diagnosed | ^~~~ ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/107388] GCC should diagnose unsigned to signed conversion with -Wconversion 2022-10-24 23:17 [Bug c++/107388] New: GCC should diagnose unsigned to signed conversion with -Wconversion nikolasklauser at berlin dot de 2022-10-24 23:20 ` [Bug c++/107388] " mpolacek at gcc dot gnu.org @ 2022-10-24 23:20 ` mpolacek at gcc dot gnu.org 2022-10-25 19:57 ` nikolasklauser at berlin dot de 2 siblings, 0 replies; 4+ messages in thread From: mpolacek at gcc dot gnu.org @ 2022-10-24 23:20 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107388 Marek Polacek <mpolacek at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|INVALID |WORKSFORME ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/107388] GCC should diagnose unsigned to signed conversion with -Wconversion 2022-10-24 23:17 [Bug c++/107388] New: GCC should diagnose unsigned to signed conversion with -Wconversion nikolasklauser at berlin dot de 2022-10-24 23:20 ` [Bug c++/107388] " mpolacek at gcc dot gnu.org 2022-10-24 23:20 ` mpolacek at gcc dot gnu.org @ 2022-10-25 19:57 ` nikolasklauser at berlin dot de 2 siblings, 0 replies; 4+ messages in thread From: nikolasklauser at berlin dot de @ 2022-10-25 19:57 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107388 --- Comment #2 from Nikolas Klauser <nikolasklauser at berlin dot de> --- Shouldn't -Wconversion also enable -Wsign-conversion? -Wconversion sounds to me like it should diagnose all conversions, especially since it's the same kind of bug I want to catch by enabling the flags. In which case would I be interested in different sizes but not different signs? ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2022-10-25 19:57 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-10-24 23:17 [Bug c++/107388] New: GCC should diagnose unsigned to signed conversion with -Wconversion nikolasklauser at berlin dot de 2022-10-24 23:20 ` [Bug c++/107388] " mpolacek at gcc dot gnu.org 2022-10-24 23:20 ` mpolacek at gcc dot gnu.org 2022-10-25 19:57 ` nikolasklauser at berlin dot de
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).