[Bug fortran/98201] CSQRT function gives bad resuts at runtime

[sgk at troutmask dot apl.washington.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98201

--- Comment #16 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Wed, Dec 09, 2020 at 01:24:20PM +0000, dpozar at ecs dot umass.edu wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98201
> 
> --- Comment #15 from dpozar at ecs dot umass.edu ---
> attached is the output file from
> 
> c:\MinGW>objdump -t c:\mingw\programs\testcsqrt.exe >cmdout.txt
> 
> don't see any reference to libraries, though.
> 

Is testcsqrt.exe compiled with the -static option?  cmdout.txt
shows

[152](sec  1)(fl 0x00)(ty  20)(scl   2) (nx 1) 0x00001210 _csqrtf
AUX tagndx 0 ttlsiz 0x0 lnnos 0 next 0

On my FreeBSD system and a static binary, I see 

% gfcx -o z -static a.f90
% objdump -t z | grep csqrt
00000000 l    df *ABS*  00000000 s_csqrtf.c
08078a90 g     F .text  0000021d csqrtf

On my FreeBSD system and a dynamic binary, I see

% gfcx -o z a.f90
% objdump -t z | grep csqrt
00000000       F *UND*  00000000              csqrtf@@FBSD_1.1

This info is sufficient to tell me that csqrtf lives in FreeBSD's libm.

objdump has several options that may help determine where
csqrtf() resides.   I don't know MingW (or windows 10) to
be of any additional help.