# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1618948804 -7200
# Node ID 5baac0b4b41c51c1e1dcf7b95f2eea01c2b1a237
# Parent  f9f7dc993602537cb65b7326f0e14cea9fd89ccd
patch 8.2.2791: Vim9: memory leak when using =expr in :substitute

Commit: https://github.com/vim/vim/commit/5c787fb7928c4cc1e7d6eec0be1bbd63d903cc8d
Author: Bram Moolenaar <Bram@vim.org>
Date:   Tue Apr 20 21:49:35 2021 +0200

    patch 8.2.2791: Vim9: memory leak when using \=expr in :substitute

    Problem:    Vim9: memory leak when using \=expr in :substitute.
    Solution:   Do not allocate a new instruction list.

diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2791,
+/**/
     2790,
 /**/
     2789,
diff --git a/src/vim9compile.c b/src/vim9compile.c
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -8544,9 +8544,7 @@ compile_substitute(char_u *arg, exarg_T 
 	    cmd = skipwhite(cmd);
 	    trailing_error = *cmd != delimiter && *cmd != NUL;
 
-	    instr_count = cctx->ctx_instr.ga_len;
-	    instr = ALLOC_MULT(isn_T, instr_count + 1);
-	    if (trailing_error || instr == NULL)
+	    if (trailing_error || ga_grow(&cctx->ctx_instr, 1) == FAIL)
 	    {
 		if (trailing_error)
 		    semsg(_(e_trailing_arg), cmd);
@@ -8559,8 +8557,8 @@ compile_substitute(char_u *arg, exarg_T 
 	    // Move the generated instructions into the ISN_SUBSTITUTE
 	    // instructions, then restore the list of instructions before
 	    // adding the ISN_SUBSTITUTE instruction.
-	    mch_memmove(instr, cctx->ctx_instr.ga_data,
-						  instr_count * sizeof(isn_T));
+	    instr_count = cctx->ctx_instr.ga_len;
+	    instr = cctx->ctx_instr.ga_data;
 	    instr[instr_count].isn_type = ISN_FINISH;
 
 	    cctx->ctx_instr = save_ga;