diff --git a/builtin/commit.c b/builtin/commit.c
index d496980421..d8abbe48b1 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -685,7 +685,7 @@ static void adjust_comment_line_char(const struct strbuf *sb)
 	const char *p;
 
 	if (!memchr(sb->buf, candidates[0], sb->len)) {
-		comment_line_char = candidates[0];
+		comment_line_str = xstrfmt("%c", candidates[0]);
 		return;
 	}
 
@@ -706,7 +706,7 @@ static void adjust_comment_line_char(const struct strbuf *sb)
 	if (!*p)
 		die(_("unable to select a comment character that is not used\n"
 		      "in the current commit message"));
-	comment_line_char = *p;
+	comment_line_str = xstrfmt("%c", *p);
 }
 
 static void prepare_amend_commit(struct commit *commit, struct strbuf *sb,
diff --git a/config.c b/config.c
index f561631374..7e5dbca4bd 100644
--- a/config.c
+++ b/config.c
@@ -1568,7 +1568,7 @@ static int git_default_core_config(const char *var, const char *value,
 		else if (value[0] && !value[1]) {
 			if (value[0] == '\n')
 				return error(_("core.commentChar cannot be newline"));
-			comment_line_char = value[0];
+			comment_line_str = xstrfmt("%c", value[0]);
 			auto_comment_line_char = 0;
 		} else
 			return error(_("core.commentChar should only be one ASCII character"));
diff --git a/environment.c b/environment.c
index 90632a39bc..0a9f5db407 100644
--- a/environment.c
+++ b/environment.c
@@ -110,7 +110,7 @@ int protect_ntfs = PROTECT_NTFS_DEFAULT;
  * The character that begins a commented line in user-editable file
  * that is subject to stripspace.
  */
-char comment_line_char = '#';
+const char *comment_line_str = "#";
 int auto_comment_line_char;
 
 /* Parallel index stat data preload? */
diff --git a/environment.h b/environment.h
index e5351c9dd9..3496474cce 100644
--- a/environment.h
+++ b/environment.h
@@ -8,7 +8,8 @@ struct strvec;
  * The character that begins a commented line in user-editable file
  * that is subject to stripspace.
  */
-extern char comment_line_char;
+#define comment_line_char (comment_line_str[0])
+extern const char *comment_line_str;
 extern int auto_comment_line_char;
 
 /*