https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63886
--- Comment #3 from David Binderman <dcb314 at hotmail dot com> --- (In reply to David Binderman from comment #2) > Given the obscurity of -Wfloat-conversion, maybe it is time for it > to be included in -Wall, where more folks will notice it ? Scratch that. While -Wfloat-conversion does check fine for int into double, it also does the "whole lot less useful, even though technically accurate" double into float message. Like float f = 3.1; warning: conversion to ‘float’ alters ‘double’ constant value [-Wfloat-conversion] I'll proceed with -Wfloat-conversion, but I'll be stripping out (fgrep -v) these unwanted warnings.