move DD_GO_TOOLCHAIN into omnibus

#31004 (comment)
#31004 (comment)

.gitlab/package_build/windows.yml

@@ -36,7 +36,6 @@
       -e BUNDLE_MIRROR__RUBYGEMS__ORG=${BUNDLE_MIRROR__RUBYGEMS__ORG}
       -e PIP_INDEX_URL=${PIP_INDEX_URL}
       -e API_KEY_ORG2=${API_KEY_ORG2}
-      -e DD_GO_TOOLCHAIN=${DD_GO_TOOLCHAIN}
       -e AGENT_FLAVOR=${AGENT_FLAVOR}
       registry.ddbuild.io/ci/datadog-agent-buildimages/windows_1809_${ARCH}${Env:DATADOG_AGENT_WINBUILDIMAGES_SUFFIX}:${Env:DATADOG_AGENT_WINBUILDIMAGES}
       c:\mnt\tasks\winbuildscripts\buildwin.bat
@@ -74,7 +73,6 @@ windows_msi_and_bosh_zip_x64-a7-fips:
   variables:
     ARCH: "x64"
     AGENT_FLAVOR: fips
-    DD_GO_TOOLCHAIN: msgo
   before_script:
     - set RELEASE_VERSION $RELEASE_VERSION_7
   timeout: 2h

omnibus/config/software/datadog-agent.rb

@@ -33,7 +33,6 @@
 
   # set GOPATH on the omnibus source dir for this software
   gopath = Pathname.new(project_dir) + '../../../..'
-  msgoroot = "/usr/local/msgo"
   flavor_arg = ENV['AGENT_FLAVOR']
   fips_args = fips_mode? ? "--fips-mode" : ""
   if windows_target?
@@ -62,9 +61,20 @@
   env = with_standard_compiler_flags(with_embedded_path(env))
 
   # Use msgo toolchain when fips mode is enabled
-  if fips_mode? && !windows_target?
-    env["GOROOT"] = msgoroot
-    env["PATH"] = "#{msgoroot}/bin:#{env['PATH']}"
+  if fips_mode?
+    if windows_target?
+      go_version = ENV['GO_VERSION'] || File.read('.go-version').strip
+      if go_version.empty?
+        raise "GO_VERSION is not set and .go-version file is not present"
+      end
+      msgoroot = "C:\\msgo\\#{go_version}\\go"
+      env["GOROOT"] = msgoroot
+      env["PATH"] = "#{msgoroot}\\bin;#{env['PATH']}"
+    else
+      msgoroot = "/usr/local/msgo"
+      env["GOROOT"] = msgoroot
+      env["PATH"] = "#{msgoroot}/bin:#{env['PATH']}"
+    end
   end
 
   # we assume the go deps are already installed before running omnibus

tasks/winbuildscripts/dobuild.bat

@@ -22,28 +22,8 @@ set REPO_ROOT=%~p0\..\..
 pushd .
 cd %REPO_ROOT% || exit /b 100
 
-REM Read .go-version file to get the default go version
-if NOT DEFINED GO_VERSION set /p GO_VERSION=<.go-version
-REM Set the GOPATH based on DD_GO_TOOLCHAIN
-if "%DD_GO_TOOLCHAIN%" == "msgo" (
-    set GOROOT=C:\msgo\%GO_VERSION%\go
-)
-if DEFINED GOROOT (
-    if NOT EXIST %GOROOT%\bin\go.exe (
-        echo go.exe not found in %GOROOT%
-        exit /b 110
-    )
-) else (
-    goto goroot_path_set
-)
-REM Use label to avoid improper expansion of PATH in IF block
-REM Put at front of path to take precedence over other go installations
-SET PATH=%GOROOT%\bin;%PATH%
-:goroot_path_set
-
 SET PATH=%PATH%;%GOPATH%\bin
 
-@echo GOROOT %GOROOT%
 @echo GOPATH %GOPATH%
 @echo PATH %PATH%
 @echo VSTUDIO_ROOT %VSTUDIO_ROOT%