diff --git a/extern/decNumber/decBasic.c b/extern/decNumber/decBasic.c
index 56396f8da7f..7645d6e658a 100644
--- a/extern/decNumber/decBasic.c
+++ b/extern/decNumber/decBasic.c
@@ -1120,7 +1120,7 @@ decFloat * decFloatAdd(decFloat *result,
   // the following buffers hold coefficients with various alignments
   // (see commentary and diagrams below)
   uByte acc[4+2+DECPMAX*3+8];
-  uByte buf[4+2+DECPMAX*2];
+  uByte buf[4+2+DECPMAX*2+4];
   uByte *umsd, *ulsd;              // local MSD and LSD pointers
 
   #if DECLITEND
diff --git a/extern/decNumber/decCommon.c b/extern/decNumber/decCommon.c
index e16d6ee2d1d..1a5df969d45 100644
--- a/extern/decNumber/decCommon.c
+++ b/extern/decNumber/decCommon.c
@@ -461,7 +461,8 @@ static decFloat * decFinalize(decFloat *df, bcdnum *num,
           uByte *t=buffer;              // safe target
           uByte *tlsd=buffer+(ulsd-umsd)+shift; // target LSD
           // printf("folddown shift=%ld\n", (LI)shift);
-          for (; s<=ulsd; s+=4, t+=4) UBFROMUI(t, UBTOUI(s));
+          for (; s+3<=ulsd; s+=4, t+=4) UBFROMUI(t, UBTOUI(s));
+          for (; s<=ulsd; s++, t++) *t=*s;
           for (t=tlsd-shift+1; t<=tlsd; t+=4) UBFROMUI(t, 0);  // pad 0s
           num->exponent-=shift;
           umsd=buffer;