[Bug c++/85861] g++ -Wconversion misses int to size_t

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85861

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2018-05-21
     Ever confirmed|0                           |1

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
You didn't provide the output of `gcc -v` as required, but I suspect you're
compiling for 32-bit, otherwise you'd get a warning:

mozilla_jwakely0/main.c: In function 'int main()':
mozilla_jwakely0/main.c:11:12: error: conversion to 'int' from 'size_t {aka
long unsigned int}' may alter its value [-Werror=conversion]
     return converted;
            ^
cc1plus: all warnings being treated as errors

For 32-bit where int and size_t are the same size you need to use
-Wsign-conversion, as documented in the manual:

  Warnings about conversions between signed and unsigned integers are
  disabled by default in C++ unless -Wsign-conversion is explicitly enabled.

https://godbolt.org/g/6J4rtS