1 files changed, 8 insertions, 0 deletions
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index 22eabc75c1..973d09d065 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -61,6 +61,7 @@ struct hl_group {
   scid_T sg_scriptID;           ///< script in which the group was last set
   // for terminal UIs
   int sg_cterm;                 ///< "cterm=" highlighting attr
+                                ///< (combination of \ref HlAttrFlags)
   int sg_cterm_fg;              ///< terminal fg color number + 1
   int sg_cterm_bg;              ///< terminal bg color number + 1
   bool sg_cterm_bold;           ///< bold attr was set for light color
@@ -2893,6 +2894,13 @@ static int syn_regexec(regmmatch_T *rmp, linenr_T lnum, colnr_T col, syn_time_T
     pt = profile_start();
   }
 
+  if (rmp->regprog == NULL) {
+    // This can happen if a previous call to vim_regexec_multi() tried to
+    // use the NFA engine, which resulted in NFA_TOO_EXPENSIVE, and
+    // compiling the pattern with the other engine fails.
+    return false;
+  }
+
   rmp->rmm_maxcol = syn_buf->b_p_smc;
   r = vim_regexec_multi(rmp, syn_win, syn_buf, lnum, col, NULL);