diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 83a8995..549d27b 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -11619,10 +11619,9 @@
 			If the system does not support deleting an environment
 			variable, it is made empty.
 
-						*:cons* *:const* *E996*
+						*:cons* *:const*
 :cons[t] {var-name} = {expr1}
 :cons[t] [{name1}, {name2}, ...] = {expr1}
-:cons[t] [{name1}, {name2}, ...] .= {expr1}
 :cons[t] [{name}, ..., ; {lastname}] = {expr1}
 :cons[t] {var-name} =<< [trim] {marker}
 text...
@@ -11641,7 +11640,11 @@
 			|:const| does not allow to for changing a variable. >
 				:let x = 1
 				:const x = 2  " Error!
-<
+<							*E996*
+			Note that environment variables, option values and
+			register values cannot be used here, since they cannot
+			be locked.
+
 :lockv[ar][!] [depth] {name} ...			*:lockvar* *:lockv*
 			Lock the internal variable {name}.  Locking means that
 			it can no longer be changed (until it is unlocked).
diff --git a/src/testdir/test_const.vim b/src/testdir/test_const.vim
index bb47e5e..d4dccb1 100644
--- a/src/testdir/test_const.vim
+++ b/src/testdir/test_const.vim
@@ -21,6 +21,21 @@
     hello
     EOS
 
+    call assert_true(exists('i'))
+    call assert_true(exists('f'))
+    call assert_true(exists('s'))
+    call assert_true(exists('F'))
+    call assert_true(exists('l'))
+    call assert_true(exists('d'))
+    if has('channel')
+        call assert_true(exists('j'))
+        call assert_true(exists('c'))
+    endif
+    call assert_true(exists('b'))
+    call assert_true(exists('n'))
+    call assert_true(exists('bl'))
+    call assert_true(exists('here'))
+
     call assert_fails('let i = 1', 'E741:')
     call assert_fails('let f = 1.1', 'E741:')
     call assert_fails('let s = "vim"', 'E741:')
@@ -218,6 +233,17 @@
     call assert_fails('const &g:encoding = "utf-8"', 'E996:')
 endfunc
 
+func Test_const_with_eval_name()
+    let s = 'foo'
+
+    " eval name with :const should work
+    const abc_{s} = 1
+    const {s}{s} = 1
+
+    let s2 = 'abc_foo'
+    call assert_fails('const {s2} = "bar"', 'E995:')
+endfunc
+
 func Test_lock_depth_is_1()
     const l = [1, 2, 3]
     const d = {'foo': 10}
diff --git a/src/version.c b/src/version.c
index aa11b7e..fcdf562 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1554,
+/**/
     1553,
 /**/
     1552,