runtime: fix a comment regarding default floating point precision

The expected precision setting for the x87 on Win32 is 53-bit
but MinGW resets the floating point unit to 64-bit.  Win32
object code generally expects values to be rounded to double,
not double extended, precision.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/8175044

diff --git a/src/pkg/runtime/asm_386.s b/src/pkg/runtime/asm_386.s
index 805405a73777189f1bd961d47d466c68e7a3b6bd..57de87b8d42d1138ddab0e37a44cb52db6e87d67 100644 (file)
--- a/src/pkg/runtime/asm_386.s
+++ b/src/pkg/runtime/asm_386.s
@@ -108,7 +108,7 @@ TEXT runtime·breakpoint(SB),7,$0
        RET
 
 TEXT runtime·asminit(SB),7,$0
-       // Linux, Windows start the FPU in extended double precision.
+       // Linux and MinGW start the FPU in extended double precision.
        // Other operating systems use double precision.
        // Change to double precision to match them,
        // and to match other hardware that only has double.