diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 617de6f..2c55e67 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -2382,9 +2382,12 @@
 	    // for '=' register: accept the rest of the line as an expression
 	    if (ea.arg[-1] == '=' && ea.arg[0] != NUL)
 	    {
-		set_expr_line(vim_strsave(ea.arg), &ea);
+		if (!ea.skip)
+		{
+		    set_expr_line(vim_strsave(ea.arg), &ea);
+		    did_set_expr_line = TRUE;
+		}
 		ea.arg += STRLEN(ea.arg);
-		did_set_expr_line = TRUE;
 	    }
 #endif
 	    ea.arg = skipwhite(ea.arg);
diff --git a/src/testdir/test_excmd.vim b/src/testdir/test_excmd.vim
index b080575..c3a911f 100644
--- a/src/testdir/test_excmd.vim
+++ b/src/testdir/test_excmd.vim
@@ -647,4 +647,12 @@
   endif
 endfunc
 
+func Test_not_break_expression_register()
+  call setreg('=', '1+1')
+  if 0
+    put =1
+  endif
+  call assert_equal('1+1', getreg('=', 1))
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index e927191..e6a4b1a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3475,
+/**/
     3474,
 /**/
     3473,