all: fix some comments

Change-Id: I163ea3a770f2228f67d4fb1374653566e64b91f7
Reviewed-on: https://go-review.googlesource.com/c/go/+/448575
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>

src/cmd/compile/internal/ir/cfg.go

@@ -5,12 +5,12 @@
 package ir
 
 var (
-	// maximum size variable which we will allocate on the stack.
+	// MaxStackVarSize is the maximum size variable which we will allocate on the stack.
 	// This limit is for explicit variable declarations like "var x T" or "x := ...".
 	// Note: the flag smallframes can update this value.
 	MaxStackVarSize = int64(10 * 1024 * 1024)
 
-	// maximum size of implicit variables that we will allocate on the stack.
+	// MaxImplicitStackVarSize is the maximum size of implicit variables that we will allocate on the stack.
 	//   p := new(T)          allocating T on the stack
 	//   p := &T{}            allocating T on the stack
 	//   s := make([]T, n)    allocating [n]T on the stack

src/net/http/transport.go

@@ -810,14 +810,12 @@ func (t *Transport) cancelRequest(key cancelKey, err error) bool {
 //
 
 var (
-	// proxyConfigOnce guards proxyConfig
 	envProxyOnce      sync.Once
 	envProxyFuncValue func(*url.URL) (*url.URL, error)
 )
 
-// defaultProxyConfig returns a ProxyConfig value looked up
-// from the environment. This mitigates expensive lookups
-// on some platforms (e.g. Windows).
+// envProxyFunc returns a function that reads the
+// environment variable to determine the proxy address.
 func envProxyFunc() func(*url.URL) (*url.URL, error) {
 	envProxyOnce.Do(func() {
 		envProxyFuncValue = httpproxy.FromEnvironment().ProxyFunc()

src/net/net.go

@@ -498,7 +498,7 @@ var (
 	// immediate cancellation of dials.
 	aLongTimeAgo = time.Unix(1, 0)
 
-	// nonDeadline and noCancel are just zero values for
+	// noDeadline and noCancel are just zero values for
 	// readability with functions taking too many parameters.
 	noDeadline = time.Time{}
 	noCancel   = (chan struct{})(nil)