https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87447
Bug ID: 87447
Summary: Missing -Wconversion warning in implicit conversion of
unsigned long long to double
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: vincent-gcc at vinc17 dot net
Target Milestone: ---
With -Wconversion, gcc does not warn on the following program, at least on
x86_64.
int foo (double x)
{
return x == (1ULL << 63) + 1;
}
Here, (1ULL << 63) + 1 is implicitly converted to double, thus with a change of
value (since double has only a 53-bit significand and (1ULL << 63) + 1 needs 64
bits). Therefore, a -Wconversion warning is expected.
Tested with:
gcc (Debian 20180822-1) 9.0.0 20180822 (experimental) [trunk revision 263760]
