!15 maint: avoid warnings from GCC8

From: @CTC-XiboWang 
Reviewed-by: @xiezhipeng1 
Signed-off-by: @xiezhipeng1

backport-maint-avoid-warnings-from-GCC8.patch

@@ -0,0 +1,85 @@
+From 040f114197ca1797bf84caedb252119c1ec07be5 Mon Sep 17 00:00:00 2001
+From: Jim Meyering <jim@meyering.net>
+Date: Fri, 6 Apr 2018 17:17:11 -0700
+Subject: [PATCH] maint: avoid warnings from GCC8
+
+Hi Andreas,
+
+I configured with --enable-gcc-warnings and bleeding-edge gcc
+(version 8.0.1 20180406) and hit some warning-escalated-to-errors.
+This fixes them:
+
+>From a71ddb200dbe7ac0f9258796b5a51979b2740e88 Mon Sep 17 00:00:00 2001
+From: Jim Meyering <meyering@fb.com>
+Date: Fri, 6 Apr 2018 16:47:00 -0700
+Subject: [PATCH] maint: avoid warnings from GCC8
+
+* src/common.h (FALLTHROUGH): Define.
+* src/patch.c (abort_hunk_context): Use FALLTHROUGH macro in place of
+a comment.  This avoids a warning from -Wimplicit-fallthrough=.
+* src/pch.c (do_ed_script): Add otherwise unnecessary initialization
+to avoid warning from -Wmaybe-uninitialized.
+(another_hunk): Use FALLTHROUGH macro here, too, twice.
+
+Conflicts:
+	src/pch.c
+---
+ src/common.h | 8 ++++++++
+ src/patch.c  | 2 +-
+ src/pch.c    | 4 ++--
+ 3 files changed, 11 insertions(+), 3 deletions(-)
+
+diff --git a/src/common.h b/src/common.h
+index 2524628..dfac17a 100644
+--- a/src/common.h
++++ b/src/common.h
+@@ -223,3 +223,11 @@ bool merge_hunk (int hunk, struct outstate *, lin where, bool *);
+ #else
+ # define merge_hunk(hunk, outstate, where, somefailed) false
+ #endif
++
++#ifndef FALLTHROUGH
++# if __GNUC__ < 7
++#  define FALLTHROUGH ((void) 0)
++# else
++#  define FALLTHROUGH __attribute__ ((__fallthrough__))
++# endif
++#endif
+diff --git a/src/patch.c b/src/patch.c
+index 065a05a..99a5904 100644
+--- a/src/patch.c
++++ b/src/patch.c
+@@ -1382,7 +1382,7 @@ abort_hunk_context (bool header, bool reverse)
+ 	    break;
+ 	case ' ': case '-': case '+': case '!':
+ 	    fprintf (rejfp, "%c ", pch_char (i));
+-	    /* fall into */
++	    FALLTHROUGH;
+ 	case '\n':
+ 	    pch_write_line (i, rejfp);
+ 	    break;
+diff --git a/src/pch.c b/src/pch.c
+index 8dda771..4368561 100644
+--- a/src/pch.c
++++ b/src/pch.c
+@@ -1742,7 +1742,7 @@ another_hunk (enum diff difftype, bool rev)
+ 		break;
+ 	    case '=':
+ 		ch = ' ';
+-		/* FALL THROUGH */
++		FALLTHROUGH;
+ 	    case ' ':
+ 		if (fillsrc > p_ptrn_lines) {
+ 		    free(s);
+@@ -1763,7 +1763,7 @@ another_hunk (enum diff difftype, bool rev)
+ 		    p_end = fillsrc-1;
+ 		    return -1;
+ 		}
+-		/* FALL THROUGH */
++		FALLTHROUGH;
+ 	    case '+':
+ 		if (filldst > p_end) {
+ 		    free(s);
+-- 
+1.8.3.1
+

patch.spec

@@ -1,6 +1,6 @@
 Name:		patch
 Version:	2.7.6
-Release:	16
+Release:	17
 Summary:	Utiliity which applies a patch file to original files.
 License:	GPLv3+
 URL:	 	http://www.gnu.org/software/patch/patch.html
@@ -17,6 +17,7 @@ Patch8:         patch-selinux.patch
 Patch9:         Avoid-set_file_attributes-sign-conversion-warnings.patch
 Patch10:        Test-suite-compatibility-fixes.patch 
 Patch11:        Test-suite-fix-Korn-shell-incompatibility.patch
+Patch12:        backport-maint-avoid-warnings-from-GCC8.patch
 
 BuildRequires:	gcc libselinux-devel libattr-devel ed
 Buildroot:	%{_tmppath}/%{name}-%{version}-%{release}-root-root
@@ -59,6 +60,9 @@ CFLAGS="$RPM_OPT_FLAGS -D_GNU_SOURCE"
 %{_mandir}/man1/*
 
 %changelog
+* Wed Dec 28 2022 Xibo.Wang <wangxb12@chinatelecom.cn> - 2.7.6-17
+- maint: avoid warnings from GCC8
+
 * Wed Dec 28 2022 Xibo.Wang <wangxb12@chinatelecom.cn> - 2.7.6-16
 - Test suite: fix Korn shell incompatibility