From 1bb6a7f6c538952b92fce424d8e015703e855147 Mon Sep 17 00:00:00 2001
From: "Darryl L. Miles" <darryl.miles@darrylmiles.org>
Date: Fri, 4 Oct 2024 19:57:57 +0100
Subject: [PATCH] plotPNM.c: warning: variable 'strip' is used uninitialized

The compiler warning concerns the use of 'goto done;' has cleanup
that accesses 'strip' before initialization.

While evaluating this I also notice the other 2 variables 'rtile'
and 'lkstep' are globals, but their pointers are not invalidated
at the time of free.

plotPNM.c:821:6: warning: variable 'strip' is used uninitialized whenever 'if' condition is true

clang18 -Wall warning cleanup [-Wsometimes-uninitialized]
---
 plot/plotPNM.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/plot/plotPNM.c b/plot/plotPNM.c
index b382e850..be620121 100644
--- a/plot/plotPNM.c
+++ b/plot/plotPNM.c
@@ -582,7 +582,7 @@ PlotPNM(fileName, scx, layers, xMask, width)
     int i, x, y, tile_ydelta;
     int save_ds, iter;
     int scale_over_2, ds_over_2;
-    float *strip;
+    float *strip = NULL;
     float scale, invscale, scaledown, normal;
 
 #ifdef VERSATEC
@@ -937,8 +937,10 @@ PlotPNM(fileName, scx, layers, xMask, width)
 done:
     PlotPNMdownsample = save_ds;
     freeMagic(rtile);
+    rtile = NULL;
     freeMagic(strip);
     freeMagic(lkstep);
+    lkstep = NULL;
     return;
 }