https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91497
--- Comment #14 from Manfred Schwarb <manfred99 at gmx dot ch> --- >FWIW, I briefly looked at conversions of complex variables >and did not find any similar -Wconversion warnings for a patched compiler. Well, I only looked at REAL,REALPART,AIMAG,IMAG,IMAGPART,DIMAG. For CMPLX, there is some warning: complex(4) ww complex(8) xx ww=CMPLX(1.0_8, 1.0_8) ww=CMPLX(1.0_8, 1.0_8, kind=4) ww=COMPLEX(1.0_8, 1.0_8) xx=CMPLX(1.0_10, 1.0_10) xx=CMPLX(1.0_10, 1.0_10, kind=8) xx=COMPLEX(1.0_10, 1.0_10) end c.f:4:15: 4 | ww=CMPLX(1.0_8, 1.0_8) | 1 Warning: Conversion from REAL(8) to default-kind COMPLEX(4) at (1) might lose precision, consider using the KIND argument [-Wconversion] c.f:7:15: 7 | xx=CMPLX(1.0_10, 1.0_10) | 1 Warning: Conversion from REAL(10) to default-kind COMPLEX(4) at (1) might lose precision, consider using the KIND argument [-Wconversion] This seems very reasonable though, no warnings when using an explicit kind statement. So no action needed here, from my point of view.