Windows build thinks sqrt (-1) == -1

As of 749740f9,

{{{ $ inplace/bin/ghc-stage2 --interactive GHCi, version 8.1.20170306: http://www.haskell.org/ghc/ :? for help Prelude> sqrt (-1) :: Double -1.0

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	highest
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system	Unknown/Multiple
Architecture

changed milestone to %8.2.1

changed weight to 10

added Tbug Trac import labels

Ummmm....

ben@schildmann MINGW64 ~/ghc$ hi.c
#include <math.h>
#include <stdio.h>

void main() { printf("%f\n", sqrt(-1)); }

ben@schildmann MINGW64 ~/ghc$ gcc hi.c -O0

ben@schildmann MINGW64 ~/ghc$ ./a.exe
-1.000000

These are relevant:

• https://sourceforge.net/p/mingw/bugs/2337/
• https://sourceforge.net/p/mingw-w64/bugs/567/

assigned to @Phyx

I'll get you a patched version later today.

added upstream label

Trac metadata

Trac field	Value
Operating system	Unknown/Multiple → Windows

Trac metadata

Trac field	Value
Differential revisions	- → D3292

removed upstream label

closed

This should be resolved in 06c8ce44.

Trac metadata

Trac field	Value
Resolution	Unresolved → ResolvedFixed

added incorrect runtime result label

added Phighest label