From d2944e6a298e824e5084ac0dfd8701ff9cd1a523 Mon Sep 17 00:00:00 2001
From: "Justin M. Keyes" <justinkz@gmail.com>
Date: Thu, 17 May 2018 08:16:58 +0200
Subject: [PATCH] mf_open(): never fails (except for OOM)

---
 src/nvim/memfile.c |  3 +--
 src/nvim/memline.c | 18 ++++++------------
 src/nvim/spell.c   |  2 +-
 3 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/src/nvim/memfile.c b/src/nvim/memfile.c
index f6e03e2532..fe4d24ba11 100644
--- a/src/nvim/memfile.c
+++ b/src/nvim/memfile.c
@@ -76,8 +76,7 @@
 
 /// @param flags  Flags for open() call.
 ///
-/// @return - The open memory file, on success.
-///         - NULL, on failure.
+/// @return The open memory file.
 memfile_T *mf_open(char_u *fname, int flags)
 {
   memfile_T *mfp = xmalloc(sizeof(memfile_T));
diff --git a/src/nvim/memline.c b/src/nvim/memline.c
index 06de9fda67..3b0cac0456 100644
--- a/src/nvim/memline.c
+++ b/src/nvim/memline.c
@@ -246,7 +246,6 @@ typedef enum {
  */
 int ml_open(buf_T *buf)
 {
-  memfile_T   *mfp;
   bhdr_T      *hp = NULL;
   ZERO_BL     *b0p;
   PTR_BL      *pp;
@@ -275,12 +274,8 @@ int ml_open(buf_T *buf)
     buf->b_may_swap = false;
   }
 
-  /*
-   * Open the memfile.  No swap file is created yet.
-   */
-  mfp = mf_open(NULL, 0);
-  if (mfp == NULL)
-    goto error;
+  // Open the memfile.  No swap file is created yet.
+  memfile_T *mfp = mf_open(NULL, 0);
 
   buf->b_ml.ml_mfp = mfp;
   buf->b_ml.ml_flags = ML_EMPTY;
@@ -364,11 +359,10 @@ int ml_open(buf_T *buf)
   return OK;
 
 error:
-  if (mfp != NULL) {
-    if (hp)
-      mf_put(mfp, hp, false, false);
-    mf_close(mfp, true);            /* will also xfree(mfp->mf_fname) */
+  if (hp) {
+    mf_put(mfp, hp, false, false);
   }
+  mf_close(mfp, true);  // will also xfree(mfp->mf_fname)
   buf->b_ml.ml_mfp = NULL;
   return FAIL;
 }
@@ -842,7 +836,7 @@ void ml_recover(void)
                                     mf_open() will consume "fname_used"! */
   mfp = mf_open(fname_used, O_RDONLY);
   fname_used = p;
-  if (mfp == NULL || mfp->mf_fd < 0) {
+  if (mfp->mf_fd < 0) {
     EMSG2(_("E306: Cannot open %s"), fname_used);
     goto theend;
   }
diff --git a/src/nvim/spell.c b/src/nvim/spell.c
index 22390557b6..686962704a 100644
--- a/src/nvim/spell.c
+++ b/src/nvim/spell.c
@@ -2488,7 +2488,7 @@ buf_T *open_spellbuf(void)
   buf->b_spell = true;
   buf->b_p_swf = true;        // may create a swap file
   if (ml_open(buf) == FAIL) {
-    ELOG("Error opening a new memline");
+    abort();
   }
   ml_open_file(buf);          // create swap file now