https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91497
--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> --- On Tue, Aug 20, 2019 at 04:12:47PM +0000, manfred99 at gmx dot ch wrote: > > --- Comment #2 from Manfred Schwarb <manfred99 at gmx dot ch> --- > Of course. But not being able to silence such warnings renders > this option rather useless, IMO. Yep. At the top of my Makefile.inc file, which all of my Makefiles pull in to set defaults, I have .ifdef EBUG CFLAGS+= -g -O FFLAGS+= -g -pipe -O -fmax-errors=1 -Werror -Wall -fcheck=all FFLAGS+= -ffpe-trap=invalid .else CFLAGS = -O2 -pipe -Wall -march=native -mtune=native FFLAGS += -O2 -pipe -march=native -mtune=native FFLAGS += -funroll-loops --param max-unroll-times=4 FFLAGS += -ftree-vectorize -Wall .endif # gfortran is too noisy FFLAGS += -Wno-maybe-uninitialized -Wno-conversion -Wno-integer-division These options produce too many false positives. > I would have expected that explicit castings would have been > special-cased in some way... > > And the manual talks explicitely about implicit conversion: > -Wconversion > Warn about implicit conversions ... Improvements to the documentation are encouraged.