diff --git a/doc/src/dihedral_hybrid.rst b/doc/src/dihedral_hybrid.rst
index add0d4d282..998a752275 100644
--- a/doc/src/dihedral_hybrid.rst
+++ b/doc/src/dihedral_hybrid.rst
@@ -57,7 +57,7 @@ If *class2* is one of the dihedral hybrid styles, the same rule holds
 for specifying additional AngleTorsion (and EndBondTorsion, etc)
 coefficients either via the input script or in the data file.
 I.e. *class2* must be added to each line after the dihedral type.  For
-lines in the AngleTorsion (or EndBondTorsion, etc) section of the data
+lines in the AngleTorsion (or EndBondTorsion, etc) Coeffs section of the data
 file for dihedral types that are not *class2*, you must use an
 dihedral style of *skip* as a placeholder, e.g.
 
diff --git a/doc/src/improper_hybrid.rst b/doc/src/improper_hybrid.rst
index cc26e14ce5..7c070d2e9c 100644
--- a/doc/src/improper_hybrid.rst
+++ b/doc/src/improper_hybrid.rst
@@ -40,13 +40,38 @@ potential with coefficients 120.0, 30 for :math:`K`, :math:`\chi_0`.
 Improper type 2 would be computed with a *cvff* potential with coefficients
 20.0, -1, 2 for K, d, and n, respectively.
 
-If the improper *class2* potential is one of the hybrid styles, it
-requires additional AngleAngle coefficients be specified in the data
-file.  These lines must also have an additional "class2" argument
-added after the improper type.  For improper types which are assigned
-to other hybrid styles, use the style name (e.g. "harmonic")
-appropriate to that style.  The AngleAngle coeffs for that improper
-type will then be ignored.
+If improper coefficients are specified in the data file read via the
+:doc:`read_data <read_data>` command, then the same rule applies.
+E.g. "harmonic" or "cvff", must be added after the improper type, for
+each line in the "Improper Coeffs" section, e.g.
+
+.. parsed-literal::
+
+   Improper Coeffs
+
+   1 harmonic 120.0 30
+   2 cvff 20.0 -1 2
+   ...
+
+If *class2* is one of the improper hybrid styles, the same rule holds
+for specifying additional AngleAngle coefficients either via the input
+script or in the data file. I.e. *class2* must be added to each line
+after the improper type.  For
+lines in the AngleAngle Coeffs section of the data
+file for dihedral types that are not *class2*, you must use an
+improper style of *skip* as a placeholder, e.g.
+
+.. parsed-literal::
+
+   AngleAngle Coeffs
+
+   1 skip
+   2 class2 0.0 0.0 0.0 115.06 130.01 115.06
+   ...
+
+Note that it is not necessary to use the improper style *skip* in the
+input script, since AngleAngle coefficients
+need not be specified at all for improper types that are not *class2*.
 
 An improper style of *none* can be specified as the second argument to
 the improper_coeff command, if you desire to turn off certain improper
diff --git a/src/pair.h b/src/pair.h
index c4a5d3678c..0c082fa1c5 100644
--- a/src/pair.h
+++ b/src/pair.h
@@ -30,6 +30,7 @@ class Pair : protected Pointers {
   friend class FixOMP;
   friend class FixQEq;
   friend class PairHybrid;
+  friend class PairHybridScaled;
   friend class ThrOMP;
   friend class Info;
 
diff --git a/src/pair_hybrid.cpp b/src/pair_hybrid.cpp
index 8f97451347..550f5c6873 100644
--- a/src/pair_hybrid.cpp
+++ b/src/pair_hybrid.cpp
@@ -569,7 +569,7 @@ void PairHybrid::init_style()
   // same style must not be used multiple times
 
   for (istyle = 0; istyle < nstyles; istyle++) {
-    bool is_gpu = (((PairHybrid *)styles[istyle])->suffix_flag & Suffix::GPU);
+    bool is_gpu = styles[istyle]->suffix_flag & Suffix::GPU;
     if (multiple[istyle] && is_gpu)
       error->all(FLERR,"GPU package styles must not be used multiple times");
   }
diff --git a/src/pair_hybrid_scaled.cpp b/src/pair_hybrid_scaled.cpp
index 90d1747075..367afe7809 100644
--- a/src/pair_hybrid_scaled.cpp
+++ b/src/pair_hybrid_scaled.cpp
@@ -340,8 +340,7 @@ void PairHybridScaled::settings(int narg, char **arg)
     special_lj[nstyles] = special_coul[nstyles] = nullptr;
     compute_tally[nstyles] = 1;
 
-    if ((((PairHybridScaled *)styles[nstyles])->suffix_flag
-         & (Suffix::INTEL|Suffix::GPU|Suffix::OMP)) != 0)
+    if ((styles[nstyles]->suffix_flag & (Suffix::INTEL|Suffix::GPU|Suffix::OMP)) != 0)
       error->all(FLERR,"Pair style hybrid/scaled does not support "
                  "accelerator styles");
 
diff --git a/src/variable.cpp b/src/variable.cpp
index 953d0ddf85..2ef1957a09 100644
--- a/src/variable.cpp
+++ b/src/variable.cpp
@@ -5122,7 +5122,7 @@ int VarReader::read_scalar(char *str)
       if (n == 1) continue;                 // skip if blank line
       break;
     }
-    memmove(str,ptr,n);                       // move trimmed string back
+    if (n > 0) memmove(str,ptr,n);                       // move trimmed string back
   }
   MPI_Bcast(&n,1,MPI_INT,0,world);
   if (n == 0) return 1;