This are the steps to reproduce my problem:

C:\>set GOPATH=C:\a\code

C:\>go get -v -d launchpad.net\goyaml
launchpad.net/goyaml (download)

C:\>cd %GOPATH%\src\launchpad.net\goyaml

C:\a\code\src\launchpad.net\goyaml>

... make small change to decode.go ...

C:\a\code\src\launchpad.net\goyaml>bzr diff
=== modified file 'decode.go'
--- decode.go   2012-03-08 21:50:15 +0000
+++ decode.go   2012-06-22 02:26:31 +0000
@@ -1,6 +1,6 @@
 package goyaml

-// #cgo LDFLAGS: -lm -lpthread
+// #cgo LDFLAGS: -lm
 // #cgo CFLAGS: -I. -DHAVE_CONFIG_H=1
 //
 // #include "helpers.h"


C:\a\code\src\launchpad.net\goyaml>go install -v
launchpad.net/goyaml
# launchpad.net/goyaml
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_alias':
decode.go:34:7: warning: assignment from incompatible pointer type
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_mapping_start':
decode.go:44:7: warning: assignment from incompatible pointer type
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_scalar':
decode.go:54:7: warning: assignment from incompatible pointer type
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_sequence_start':
decode.go:64:7: warning: assignment from incompatible pointer type

C:\a\code\src\launchpad.net\goyaml>go install -x
WORK=C:\DOCUME~1\brainman\LOCALS~1\Temp\go-build480094247
mkdir -p $WORK\launchpad.net\goyaml\_obj\
cd C:\a\code\src\launchpad.net\goyaml
c:\mingw\go\pkg\tool\windows_386\cgo.exe -objdir $WORK\launchpad.net\goyaml\_obj\ -- -I.
-DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\ decode.go encode.go
c:\mingw\go\pkg\tool\windows_386\8c.exe -FVw -I $WORK\launchpad.net\goyaml\_obj\ -I
c:\mingw\go\pkg\windows_386 -o $WORK\launchpad.net\goyaml\_obj\_cgo_defun.8
-DGOOS_windows -DGOARCH_386 $WORK\launchpad.net\goyaml\_obj\_cgo_defun.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\_cgo_main.o -c
$WORK\launchpad.net\goyaml\_obj\_cgo_main.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\_cgo_export.o -c
$WORK\launchpad.net\goyaml\_obj\_cgo_export.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\decode.cgo2.o -c
$WORK\launchpad.net\goyaml\_obj\decode.cgo2.c
# launchpad.net/goyaml
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_alias':
decode.go:34:7: warning: assignment from incompatible pointer type
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_mapping_start':
decode.go:44:7: warning: assignment from incompatible pointer type
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_scalar':
decode.go:54:7: warning: assignment from incompatible pointer type
decode.go: In function '_cgo_e6ee69cb7fed_Cfunc_event_sequence_start':
decode.go:64:7: warning: assignment from incompatible pointer type
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\encode.cgo2.o -c
$WORK\launchpad.net\goyaml\_obj\encode.cgo2.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\api.o -c .\api.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\emitter.o -c .\emitter.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\helpers.o -c .\helpers.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\loader.o -c .\loader.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\parser.o -c .\parser.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\reader.o -c .\reader.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\scanner.o -c .\scanner.c
gcc -I . -g -O2 -m32 -mthreads -I. -DHAVE_CONFIG_H=1 -I $WORK\launchpad.net\goyaml\_obj\
-o $WORK\launchpad.net\goyaml\_obj\writer.o -c .\writer.c
gcc -I . -g -O2 -m32 -mthreads -o $WORK\launchpad.net\goyaml\_obj\_cgo_.o
$WORK\launchpad.net\goyaml\_obj\_cgo_main.o
$WORK\launchpad.net\goyaml\_obj\_cgo_export.o
$WORK\launchpad.net\goyaml\_obj\decode.cgo2.o
$WORK\launchpad.net\goyaml\_obj\encode.cgo2.o $WORK\launchpad.net\goyaml\_obj\api.o
$WORK\launchpad.net\goyaml\_obj\emitter.o $WORK\launchpad.net\goyaml\_obj\helpers.o
$WORK\launchpad.net\goyaml\_obj\loader.o $WORK\launchpad.net\goyaml\_obj\parser.o
$WORK\launchpad.net\goyaml\_obj\reader.o $WORK\launchpad.net\goyaml\_obj\scanner.o
$WORK\launchpad.net\goyaml\_obj\writer.o -lm

C:\a\code\src\launchpad.net\goyaml>

Last gcc link step fails, but it prints no error messages. There are a lot of these
error messages and they all written to stdout by Go together in one write. This write
seems to fail.

We had this problem reported before: https://golang.org/issue/3376.
But Russ hijacked conversation there into something else :-)

I propose we make change in os package. I will find a buffer size that is big enough and
works, and we will change stdout and stderr os.write to do multiple writes if buffer is
bigger then predefined.

Alex