diff --git a/src/cmd/go/internal/load/test.go b/src/cmd/go/internal/load/test.go
index afff5deaaa..2864fb5ebb 100644
--- a/src/cmd/go/internal/load/test.go
+++ b/src/cmd/go/internal/load/test.go
@@ -399,10 +399,13 @@ func recompileForTest(pmain, preal, ptest, pxtest *Package) {
 			}
 		}
 
-		// Don't compile build info from a main package. This can happen
-		// if -coverpkg patterns include main packages, since those packages
-		// are imported by pmain. See golang.org/issue/30907.
-		if p.Internal.BuildInfo != "" && p != pmain {
+		// Force main packages the test imports to be built as libraries.
+		// Normal imports of main packages are forbidden by the package loader,
+		// but this can still happen if -coverpkg patterns include main packages:
+		// covered packages are imported by pmain. Linking multiple packages
+		// compiled with '-p main' causes duplicate symbol errors.
+		// See golang.org/issue/30907, golang.org/issue/34114.
+		if p.Name == "main" && p != pmain {
 			split()
 		}
 	}
diff --git a/src/cmd/go/testdata/script/cover_pkgall_multiple_mains.txt b/src/cmd/go/testdata/script/cover_pkgall_multiple_mains.txt
index ab7cd66949..f21cd8b3a8 100644
--- a/src/cmd/go/testdata/script/cover_pkgall_multiple_mains.txt
+++ b/src/cmd/go/testdata/script/cover_pkgall_multiple_mains.txt
@@ -1,29 +1,32 @@
 # This test checks that multiple main packages can be tested
 # with -coverpkg=all without duplicate symbol errors.
-# Verifies golang.org/issue/30374.
-
-env GO111MODULE=on
+# Verifies golang.org/issue/30374, golang.org/issue/34114.
 
 [short] skip
+cd $GOPATH/src/example.com/cov
 
+env GO111MODULE=on
 go test -coverpkg=all ./...
 
--- go.mod --
+env GO111MODULE=off
+go test -coverpkg=all ./...
+
+-- $GOPATH/src/example.com/cov/go.mod --
 module example.com/cov
 
--- mainonly/mainonly.go --
+-- $GOPATH/src/example.com/cov/mainonly/mainonly.go --
 package main
 
 func main() {}
 
--- mainwithtest/mainwithtest.go --
+-- $GOPATH/src/example.com/cov/mainwithtest/mainwithtest.go --
 package main
 
 func main() {}
 
 func Foo() {}
 
--- mainwithtest/mainwithtest_test.go --
+-- $GOPATH/src/example.com/cov/mainwithtest/mainwithtest_test.go --
 package main
 
 import "testing"
@@ -32,10 +35,10 @@ func TestFoo(t *testing.T) {
   Foo()
 }
 
--- xtest/x.go --
+-- $GOPATH/src/example.com/cov/xtest/x.go --
 package x
 
--- xtest/x_test.go --
+-- $GOPATH/src/example.com/cov/xtest/x_test.go --
 package x_test
 
 import "testing"