1The 4.09.1 tarball appears to have been acidentally generated as a
2development tarball, which causes configure to enable -Werror. This
3means newer compilers will make the build fail.
4
5diff a/configure b/configure
6--- a/configure
7+++ b/configure
8@@ -12360,7 +12360,7 @@ case $ocaml_cv_cc_vendor in #(
9 msvc-*) :
10 outputobj=-Fo; CPP="cl -nologo -EP"; gcc_warnings="" ;; #(
11 *) :
12- outputobj='-o $(EMPTY)'; case 4.09.1+dev1-2020-03-13 in #(
13+ outputobj='-o $(EMPTY)'; case 4.09.1 in #(
14 *+dev*) :
15 gcc_warnings="-Wall -Werror" ;; #(
16 *) :