ocaml: introduce patch to remove unused var to enable ptest (#2348)

Reference: https://github.com/ocaml/ocaml/pull/11067

Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>

SPECS/ocaml/0004-remove-unused-var-in-alloc_aync_stubs.patch

@@ -0,0 +1,22 @@
+From 5765c7ecd4554d46b8ef3bcc312d00d270fe6e24 Mon Sep 17 00:00:00 2001
+From: Jerry James <loganjerry@gmail.com>
+Date: Sat, 26 Feb 2022 20:09:16 -0700
+Subject: [PATCH] Remove an unused variable in alloc_async_stubs.c
+
+---
+ testsuite/tests/c-api/alloc_async_stubs.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/testsuite/tests/c-api/alloc_async_stubs.c b/testsuite/tests/c-api/alloc_async_stubs.c
+index 7dfbeb4caae..b3c6bccf249 100644
+--- a/testsuite/tests/c-api/alloc_async_stubs.c
++++ b/testsuite/tests/c-api/alloc_async_stubs.c
+@@ -8,7 +8,7 @@ value stub(value ref)
+ {
+   CAMLparam1(ref);
+   CAMLlocal2(x, y);
+-  int i; char* s; intnat coll_before;
++  char* s; intnat coll_before;
+ 
+   printf("C, before: %d\n", Int_val(Field(ref, 0)));
+ 

SPECS/ocaml/ocaml.spec

@@ -4,7 +4,7 @@
 Summary:        OCaml compiler and programming environment
 Name:           ocaml
 Version:        4.13.1
-Release:        1%{?dist}
+Release:        2%{?dist}
 License:        QPL and (LGPLv2+ with exceptions)
 Vendor:         Microsoft Corporation
 Distribution:   Mariner
@@ -13,6 +13,7 @@ Source0:        https://caml.inria.fr/pub/distrib/%{name}-%{majmin}/%{name}-%{ve
 Patch0001:      0001-Don-t-add-rpaths-to-libraries.patch
 Patch0002:      0002-configure-Allow-user-defined-C-compiler-flags.patch
 Patch0003:      0003-configure-Remove-incorrect-assumption-about-cross-co.patch
+Patch0004:      0004-remove-unused-var-in-alloc_aync_stubs.patch
 BuildRequires:  autoconf
 BuildRequires:  binutils-devel
 BuildRequires:  chrpath
@@ -257,6 +258,9 @@ make -j1 all
 %{_libdir}/ocaml/compiler-libs/*.o
 
 %changelog
+* Mon Feb 28 2022 Muhammad Falak <mwani@microsoft.com> - 4.13.1-2
+- Introduce a patch to remove unused vars in test to enable ptest
+
 * Mon Jan 10 2022 Thomas Crain <thcrain@microsoft.com> - 4.13.1-1
 - Upgrade to latest upstream release and rebase relevant patches
 - Remove arch-specific gating- only applies to arches Mariner does not support