From 641a440ec6229c1d368b9ead48f4968b955c0115 Mon Sep 17 00:00:00 2001
From: Yves Orton <demerphq@gmail.com>
Date: Thu, 17 Feb 2022 03:32:54 +0100
Subject: [PATCH] Fix Issue #4 - Silence uninitialized warnings
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Since cost is not initialized and the compiler cannot tell
if they are properly initialized (they are) warnings are produced
when building in blead perl under certain compilers.

This patch silences the warnings by making sure the data structures
are initialized to 0.

Warnings silenced:

    gcc -c  -I. -D_REENTRANT -D_GNU_SOURCE -fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -Wall -Werror=pointer-arith -Werror=vla -Wextra -Wno-long-long -Wno-declaration-after-statement -Wc++-compat -Wwrite-strings -O3   -DVERSION=\"2.101\" -DXS_VERSION=\"2.101\" -fPIC "-I../.."  -Wall -Wno-comment  -DBZ_NO_STDIO  compress.c
    compress.c: In function ‘BZ2_compressBlock’:
    compress.c:392:54: warning: ‘cost[5]’ may be used uninitialized in this function [-Wmaybe-uninitialized]
		    for (t = 0; t < nGroups; t++) cost[t] += s->len[t][icv];
							  ^~
    compress.c:256:11: note: ‘cost[5]’ was declared here
	UInt16 cost[BZ_N_GROUPS];
	       ^~~~
    compress.c:402:21: warning: ‘cost[3]’ may be used uninitialized in this function [-Wmaybe-uninitialized]
		 if (cost[t] < bc) { bc = cost[t]; bt = t; };
		     ~~~~^~~
    compress.c:256:11: note: ‘cost[3]’ was declared here
	UInt16 cost[BZ_N_GROUPS];
	       ^~~~
    compress.c:402:21: warning: ‘cost[2]’ may be used uninitialized in this function [-Wmaybe-uninitialized]
		 if (cost[t] < bc) { bc = cost[t]; bt = t; };
		     ~~~~^~~
    compress.c:256:11: note: ‘cost[2]’ was declared here
	UInt16 cost[BZ_N_GROUPS];
	       ^~~~
---
 bzip2-src/compress.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/bzip2-src/compress.c b/bzip2-src/compress.c
index 84e1574..1666cf0 100644
--- a/bzip2-src/compress.c
+++ b/bzip2-src/compress.c
@@ -253,8 +253,8 @@ void sendMTFValues ( EState* s )
    --*/
 
 
-   UInt16 cost[BZ_N_GROUPS];
-   Int32  fave[BZ_N_GROUPS];
+   UInt16 cost[BZ_N_GROUPS] = {0, 0, 0, 0, 0, 0};
+   Int32  fave[BZ_N_GROUPS] = {0, 0, 0, 0, 0, 0};
 
    UInt16* mtfv = s->mtfv;