diff --git a/flang/runtime/character.cpp b/flang/runtime/character.cpp
--- a/flang/runtime/character.cpp
+++ b/flang/runtime/character.cpp
@@ -188,7 +188,7 @@
     AdjustLRHelper<char32_t, ADJUSTR>(result, string, terminator);
     break;
   default:
-    terminator.Crash("ADJUSTL/R: bad string type code %d",
+    terminator.Crash("ADJUSTL/R: invalid string type code %d",
         static_cast<int>(string.raw().type));
   }
 }
@@ -253,7 +253,7 @@
         result, string, terminator);
     break;
   default:
-    terminator.Crash("LEN_TRIM: bad KIND=%d", kind);
+    terminator.Crash("LEN_TRIM: unsupported KIND=%d", kind);
   }
 }
 
@@ -454,7 +454,7 @@
         result, string, arg, back, terminator);
     break;
   default:
-    terminator.Crash("INDEX/SCAN/VERIFY: bad KIND=%d", kind);
+    terminator.Crash("INDEX/SCAN/VERIFY: unsupported KIND=%d", kind);
   }
 }
 
@@ -783,7 +783,7 @@
         y.OffsetElement<char32_t>(), x.ElementBytes() >> 2,
         y.ElementBytes() >> 2);
   default:
-    terminator.Crash("CharacterCompareScalar: bad string type code %d",
+    terminator.Crash("CharacterCompareScalar: invalid string type code %d",
         static_cast<int>(x.raw().type));
   }
   return 0;
@@ -819,7 +819,7 @@
     Compare<char32_t>(result, x, y, terminator);
     break;
   default:
-    terminator.Crash("CharacterCompareScalar: bad string type code %d",
+    terminator.Crash("CharacterCompareScalar: invalid string type code %d",
         static_cast<int>(x.raw().type));
   }
 }
@@ -882,8 +882,8 @@
         result, string, substring, back, kind, terminator);
     break;
   default:
-    terminator.Crash(
-        "INDEX: bad string type code %d", static_cast<int>(string.raw().type));
+    terminator.Crash("INDEX: invalid string type code %d",
+        static_cast<int>(string.raw().type));
   }
 }
 
@@ -911,7 +911,7 @@
     LenTrimKind<char32_t>(result, string, kind, terminator);
     break;
   default:
-    terminator.Crash("LEN_TRIM: bad string type code %d",
+    terminator.Crash("LEN_TRIM: invalid string type code %d",
         static_cast<int>(string.raw().type));
   }
 }
@@ -947,8 +947,8 @@
         result, string, set, back, kind, terminator);
     break;
   default:
-    terminator.Crash(
-        "SCAN: bad string type code %d", static_cast<int>(string.raw().type));
+    terminator.Crash("SCAN: invalid string type code %d",
+        static_cast<int>(string.raw().type));
   }
 }
 
@@ -987,8 +987,8 @@
         << 2;
     break;
   default:
-    terminator.Crash(
-        "TRIM: bad string type code %d", static_cast<int>(string.raw().type));
+    terminator.Crash("TRIM: invalid string type code %d",
+        static_cast<int>(string.raw().type));
   }
   result.Establish(string.type(), resultBytes, nullptr, 0, nullptr,
       CFI_attribute_allocatable);
@@ -1027,8 +1027,8 @@
         result, string, set, back, kind, terminator);
     break;
   default:
-    terminator.Crash(
-        "VERIFY: bad string type code %d", static_cast<int>(string.raw().type));
+    terminator.Crash("VERIFY: invalid string type code %d",
+        static_cast<int>(string.raw().type));
   }
 }
 
diff --git a/flang/runtime/descriptor-io.h b/flang/runtime/descriptor-io.h
--- a/flang/runtime/descriptor-io.h
+++ b/flang/runtime/descriptor-io.h
@@ -480,7 +480,7 @@
       return FormattedDerivedTypeIO<DIR>(io, descriptor);
     }
   }
-  handler.Crash("DescriptorIO: Bad type code (%d) in descriptor",
+  handler.Crash("DescriptorIO: invalid type code (%d) in descriptor",
       static_cast<int>(descriptor.type().raw()));
   return false;
 }
diff --git a/flang/runtime/dot-product.cpp b/flang/runtime/dot-product.cpp
--- a/flang/runtime/dot-product.cpp
+++ b/flang/runtime/dot-product.cpp
@@ -117,7 +117,7 @@
           }
         }
         terminator.Crash(
-            "DOT_PRODUCT(%d(%d)): bad operand types (%d(%d), %d(%d))",
+            "DOT_PRODUCT(%d(%d)): invalid operand types (%d(%d), %d(%d))",
             static_cast<int>(RCAT), RKIND, static_cast<int>(XCAT), XKIND,
             static_cast<int>(YCAT), YKIND);
       }
diff --git a/flang/runtime/edit-input.cpp b/flang/runtime/edit-input.cpp
--- a/flang/runtime/edit-input.cpp
+++ b/flang/runtime/edit-input.cpp
@@ -37,7 +37,7 @@
       digit = ch + 10 - 'a';
     } else {
       io.GetIoErrorHandler().SignalError(
-          "Bad character '%lc' in B/O/Z input field", ch);
+          "Invalid character '%lc' in B/O/Z input field", ch);
       return false;
     }
     value *= base;
@@ -115,7 +115,7 @@
       digit = ch - '0';
     } else {
       io.GetIoErrorHandler().SignalError(
-          "Bad character '%lc' in INTEGER input field", ch);
+          "Invalid character '%lc' in INTEGER input field", ch);
       return false;
     }
     value *= 10;
@@ -349,7 +349,7 @@
     return false;
   }
   if (got == 0) {
-    io.GetIoErrorHandler().SignalError("Bad REAL input value");
+    io.GetIoErrorHandler().SignalError("Invalid REAL input value");
     return false;
   }
   bool hadExtra{got > maxDigits};
@@ -474,7 +474,7 @@
     break;
   default:
     io.GetIoErrorHandler().SignalError(
-        "Bad character '%lc' in LOGICAL input field", *next);
+        "Invalid character '%lc' in LOGICAL input field", *next);
     return false;
   }
   if (remaining) { // ignore the rest of the field
diff --git a/flang/runtime/extrema.cpp b/flang/runtime/extrema.cpp
--- a/flang/runtime/extrema.cpp
+++ b/flang/runtime/extrema.cpp
@@ -176,7 +176,7 @@
     break;
   default:
     terminator.Crash(
-        "%s: Bad data type code (%d) for array", intrinsic, x.type().raw());
+        "%s: invalid data type code (%d) for array", intrinsic, x.type().raw());
   }
 }
 
@@ -262,7 +262,7 @@
     break;
   default:
     terminator.Crash(
-        "%s: Bad data type code (%d) for array", intrinsic, x.type().raw());
+        "%s: invalid data type code (%d) for array", intrinsic, x.type().raw());
   }
 }
 
@@ -391,7 +391,7 @@
         type->second, terminator, result, x, dim, mask, intrinsic, terminator);
     break;
   default:
-    terminator.Crash("%s: bad type code %d", intrinsic, x.type().raw());
+    terminator.Crash("%s: invalid type code %d", intrinsic, x.type().raw());
   }
 }
 
@@ -674,7 +674,7 @@
     ApplyFloatingPointKind<Norm2Helper, void>(
         type->second, terminator, result, x, dim, mask, terminator);
   } else {
-    terminator.Crash("NORM2: bad type code %d", x.type().raw());
+    terminator.Crash("NORM2: invalid type code %d", x.type().raw());
   }
 }
 } // extern "C"
diff --git a/flang/runtime/findloc.cpp b/flang/runtime/findloc.cpp
--- a/flang/runtime/findloc.cpp
+++ b/flang/runtime/findloc.cpp
@@ -169,7 +169,7 @@
         break;
       default:
         terminator.Crash(
-            "FINDLOC: bad target category %d for array category %d",
+            "FINDLOC: invalid target category %d for array category %d",
             static_cast<int>(targetCat), static_cast<int>(CAT));
       }
     }
@@ -248,7 +248,7 @@
     break;
   default:
     terminator.Crash(
-        "FINDLOC: Bad data type code (%d) for array", x.type().raw());
+        "FINDLOC: invalid data type code (%d) for array", x.type().raw());
   }
 }
 } // extern "C"
@@ -335,7 +335,7 @@
     break;
   default:
     terminator.Crash(
-        "FINDLOC: Bad data type code (%d) for array", x.type().raw());
+        "FINDLOC: invalid data type code (%d) for array", x.type().raw());
   }
 }
 } // extern "C"
diff --git a/flang/runtime/inquiry.cpp b/flang/runtime/inquiry.cpp
--- a/flang/runtime/inquiry.cpp
+++ b/flang/runtime/inquiry.cpp
@@ -23,7 +23,8 @@
     const Descriptor &array, int dim, const char *sourceFile, int line) {
   if (dim < 1 || dim > array.rank()) {
     Terminator terminator{sourceFile, line};
-    terminator.Crash("SIZE: bad DIM=%d", dim);
+    terminator.Crash(
+        "SIZE: invalid DIM=%d for ARRAY with rank=%d", dim, array.rank());
   }
   const Dimension &dimension{array.GetDimension(dim - 1)};
   return static_cast<std::int64_t>(dimension.LowerBound());
@@ -68,7 +69,8 @@
     const Descriptor &array, int dim, const char *sourceFile, int line) {
   if (dim < 1 || dim > array.rank()) {
     Terminator terminator{sourceFile, line};
-    terminator.Crash("SIZE: bad DIM=%d", dim);
+    terminator.Crash(
+        "SIZE: invalid DIM=%d for ARRAY with rank=%d", dim, array.rank());
   }
   const Dimension &dimension{array.GetDimension(dim - 1)};
   return static_cast<std::int64_t>(dimension.Extent());
diff --git a/flang/runtime/io-api.cpp b/flang/runtime/io-api.cpp
--- a/flang/runtime/io-api.cpp
+++ b/flang/runtime/io-api.cpp
@@ -564,7 +564,7 @@
     unit->SetPosition(pos - 1, handler);
     return true;
   }
-  io.GetIoErrorHandler().Crash("SetPos() on internal unit");
+  io.GetIoErrorHandler().Crash("SetPos() called on internal unit");
   return false;
 }
 
@@ -937,8 +937,9 @@
   }
   std::int64_t result{open->unit().unitNumber()};
   if (!SetInteger(unit, kind, result)) {
-    open->SignalError("GetNewUnit(): Bad INTEGER kind(%d) or out-of-range "
-                      "value(%jd) for result",
+    open->SignalError(
+        "GetNewUnit(): Unsupported INTEGER kind(%d) or out-of-range "
+        "value(%jd) for result",
         kind, static_cast<std::intmax_t>(result));
   }
   return true;
@@ -1209,7 +1210,8 @@
       return true;
     }
     io.GetIoErrorHandler().SignalError(
-        "InquireInteger64(): Bad INTEGER kind(%d) or out-of-range value(%jd) "
+        "InquireInteger64(): Unsupported INTEGER kind(%d) or out-of-range "
+        "value(%jd) "
         "for result",
         kind, static_cast<std::intmax_t>(n));
   }
diff --git a/flang/runtime/io-stmt.cpp b/flang/runtime/io-stmt.cpp
--- a/flang/runtime/io-stmt.cpp
+++ b/flang/runtime/io-stmt.cpp
@@ -78,7 +78,7 @@
 void IoStatementBase::BadInquiryKeywordHashCrash(InquiryKeywordHash inquiry) {
   char buffer[16];
   const char *decode{InquiryKeywordHashDecode(buffer, sizeof buffer, inquiry)};
-  Crash("bad InquiryKeywordHash 0x%x (%s)", inquiry,
+  Crash("invalid InquiryKeywordHash 0x%x (%s)", inquiry,
       decode ? decode : "(cannot decode)");
 }
 
diff --git a/flang/runtime/iostat.cpp b/flang/runtime/iostat.cpp
--- a/flang/runtime/iostat.cpp
+++ b/flang/runtime/iostat.cpp
@@ -32,13 +32,13 @@
   case IostatErrorInFormat:
     return "Invalid FORMAT";
   case IostatErrorInKeyword:
-    return "Bad keyword argument value";
+    return "Invalid keyword argument value";
   case IostatEndfileDirect:
     return "ENDFILE on direct-access file";
   case IostatEndfileUnwritable:
     return "ENDFILE on read-only file";
   case IostatOpenBadRecl:
-    return "OPEN with bad RECL= value";
+    return "OPEN with invalid RECL= value";
   case IostatOpenUnknownSize:
     return "OPEN of file of unknown size";
   case IostatOpenBadAppend:
diff --git a/flang/runtime/matmul.cpp b/flang/runtime/matmul.cpp
--- a/flang/runtime/matmul.cpp
+++ b/flang/runtime/matmul.cpp
@@ -159,7 +159,7 @@
   int yRank{y.rank()};
   int resRank{xRank + yRank - 2};
   if (xRank * yRank != 2 * resRank) {
-    terminator.Crash("MATMUL: bad argument ranks (%d * %d)", xRank, yRank);
+    terminator.Crash("MATMUL: invalid argument ranks (%d * %d)", xRank, yRank);
   }
   SubscriptValue extent[2]{
       xRank == 2 ? x.GetDimension(0).Extent() : y.GetDimension(1).Extent(),
@@ -316,7 +316,7 @@
                 CppTypeFor<YCAT, YKIND>>(result, x, y, terminator);
           }
         }
-        terminator.Crash("MATMUL: bad operand types (%d(%d), %d(%d))",
+        terminator.Crash("MATMUL: invalid operand types (%d(%d), %d(%d))",
             static_cast<int>(XCAT), XKIND, static_cast<int>(YCAT), YKIND);
       }
     };
diff --git a/flang/runtime/namelist.cpp b/flang/runtime/namelist.cpp
--- a/flang/runtime/namelist.cpp
+++ b/flang/runtime/namelist.cpp
@@ -225,11 +225,11 @@
         return true;
       } else {
         handler.SignalError(
-            "Bad subscripts for NAMELIST input group item '%s'", name);
+            "Invalid subscripts for NAMELIST input group item '%s'", name);
       }
     } else {
       handler.SignalError(
-          "Bad subscripts (missing ')') for NAMELIST input group item '%s'",
+          "Invalid subscripts (missing ')') for NAMELIST input group item '%s'",
           name);
     }
   }
@@ -289,10 +289,11 @@
       }
     }
     handler.SignalError(
-        "Bad substring bounds for NAMELIST input group item '%s'", name);
+        "Invalid substring bounds for NAMELIST input group item '%s'", name);
   } else {
     handler.SignalError(
-        "Bad substring (missing ')') for NAMELIST input group item '%s'", name);
+        "Invalid substring (missing ')') for NAMELIST input group item '%s'",
+        name);
   }
   return false;
 }
diff --git a/flang/runtime/random.cpp b/flang/runtime/random.cpp
--- a/flang/runtime/random.cpp
+++ b/flang/runtime/random.cpp
@@ -127,7 +127,7 @@
     *size.OffsetElement<CppTypeFor<TypeCategory::Integer, 8>>() = 1;
     break;
   default:
-    terminator.Crash("RANDOM_SEED(SIZE=): bad kind %d\n", kind);
+    terminator.Crash("RANDOM_SEED(SIZE=): unsupported kind %d\n", kind);
   }
 }
 
@@ -148,7 +148,7 @@
     seed = *put.OffsetElement<CppTypeFor<TypeCategory::Integer, 8>>();
     break;
   default:
-    terminator.Crash("RANDOM_SEED(PUT=): bad kind %d\n", kind);
+    terminator.Crash("RANDOM_SEED(PUT=): unsupported kind %d\n", kind);
   }
   {
     CriticalSection critical{lock};
@@ -186,7 +186,7 @@
     *got.OffsetElement<CppTypeFor<TypeCategory::Integer, 8>>() = seed;
     break;
   default:
-    terminator.Crash("RANDOM_SEED(GET=): bad kind %d\n", kind);
+    terminator.Crash("RANDOM_SEED(GET=): unsupported kind %d\n", kind);
   }
 }
 } // extern "C"
diff --git a/flang/runtime/reduction-templates.h b/flang/runtime/reduction-templates.h
--- a/flang/runtime/reduction-templates.h
+++ b/flang/runtime/reduction-templates.h
@@ -44,8 +44,8 @@
     const Descriptor *mask, ACCUMULATOR &accumulator, const char *intrinsic,
     Terminator &terminator) {
   if (dim < 0 || dim > 1) {
-    terminator.Crash(
-        "%s: bad DIM=%d for argument with rank %d", intrinsic, dim, x.rank());
+    terminator.Crash("%s: invalid DIM=%d for ARRAY argument with rank %d",
+        intrinsic, dim, x.rank());
   }
   SubscriptValue xAt[maxRank];
   x.GetLowerBounds(xAt);
@@ -166,7 +166,8 @@
     TypeCode typeCode) {
   int xRank{x.rank()};
   if (dim < 1 || dim > xRank) {
-    terminator.Crash("%s: bad DIM=%d for rank %d", intrinsic, dim, xRank);
+    terminator.Crash(
+        "%s: invalid DIM=%d for ARRAY with rank %d", intrinsic, dim, xRank);
   }
   int zeroBasedDim{dim - 1};
   SubscriptValue resultExtent[maxRank];
diff --git a/flang/runtime/reduction.cpp b/flang/runtime/reduction.cpp
--- a/flang/runtime/reduction.cpp
+++ b/flang/runtime/reduction.cpp
@@ -228,7 +228,8 @@
     typename ACCUMULATOR::Type {
   Terminator terminator{source, line};
   if (dim < 0 || dim > 1) {
-    terminator.Crash("%s: bad DIM=%d", intrinsic, dim);
+    terminator.Crash(
+        "%s: invalid DIM=%d for ARRAY with rank=1", intrinsic, dim);
   }
   SubscriptValue xAt[maxRank];
   x.GetLowerBounds(xAt);
diff --git a/flang/runtime/tools.cpp b/flang/runtime/tools.cpp
--- a/flang/runtime/tools.cpp
+++ b/flang/runtime/tools.cpp
@@ -106,7 +106,7 @@
 
 void CheckIntegerKind(Terminator &terminator, int kind, const char *intrinsic) {
   if (kind < 1 || kind > 16 || (kind & (kind - 1)) != 0) {
-    terminator.Crash("%s: bad KIND=%d argument", intrinsic, kind);
+    terminator.Crash("%s: invalid KIND=%d argument", intrinsic, kind);
   }
 }
 } // namespace Fortran::runtime
diff --git a/flang/runtime/transformational.cpp b/flang/runtime/transformational.cpp
--- a/flang/runtime/transformational.cpp
+++ b/flang/runtime/transformational.cpp
@@ -102,7 +102,7 @@
           static_cast<char32_t>(' '));
       break;
     default:
-      terminator.Crash("EOSHIFT: bad CHARACTER kind %d", kind);
+      terminator.Crash("EOSHIFT: unsupported CHARACTER kind %d", kind);
     }
   } else {
     std::memset(result.raw().base_addr, 0, bytes);
@@ -379,7 +379,7 @@
         shape.Element<char>(&shapeSubscript), shapeElementBytes, terminator);
     if (resultExtent[j] < 0)
       terminator.Crash(
-          "RESHAPE: bad value for SHAPE(%d)=%d", j + 1, resultExtent[j]);
+          "RESHAPE: invalid value for SHAPE(%d)=%d", j + 1, resultExtent[j]);
     resultElements *= resultExtent[j];
   }
 
@@ -412,7 +412,7 @@
       auto k{GetInt64(order->Element<char>(&orderSubscript), orderElementBytes,
           terminator)};
       if (k < 1 || k > resultRank || ((values >> k) & 1))
-        terminator.Crash("RESHAPE: bad value for ORDER element (%d)", k);
+        terminator.Crash("RESHAPE: invalid value for ORDER element (%d)", k);
       values |= std::uint64_t{1} << k;
       dimOrder[j] = k - 1;
     }
@@ -525,12 +525,15 @@
   }
   mask.GetLowerBounds(maskAt);
   field.GetLowerBounds(fieldAt);
-  SubscriptValue vectorLeft{vector.GetDimension(0).Extent()};
+  SubscriptValue vectorElements{vector.GetDimension(0).Extent()};
+  SubscriptValue vectorLeft{vectorElements};
   for (std::size_t n{result.Elements()}; n-- > 0;) {
     if (IsLogicalElementTrue(mask, maskAt)) {
       if (vectorLeft-- == 0) {
-        terminator.Crash("UNPACK: VECTOR= argument has fewer elements than "
-                         "MASK= has .TRUE. entries");
+        terminator.Crash(
+            "UNPACK: VECTOR= argument has fewer elements (%d) than "
+            "MASK= has .TRUE. entries",
+            vectorElements);
       }
       CopyElement(result, resultAt, vector, &vectorAt, terminator);
       ++vectorAt;
diff --git a/flang/runtime/type-info.cpp b/flang/runtime/type-info.cpp
--- a/flang/runtime/type-info.cpp
+++ b/flang/runtime/type-info.cpp
@@ -170,7 +170,7 @@
       desc.OffsetElement() != nullptr) {
     std::fwrite(desc.OffsetElement(), desc.ElementBytes(), 1, f);
   } else {
-    std::fprintf(f, "bad %s descriptor: ", what);
+    std::fprintf(f, "invalid %s descriptor: ", what);
     desc.Dump(f);
   }
 }
@@ -227,7 +227,7 @@
       comp.Dump(f);
     }
   } else {
-    std::fputs("    bad descriptor: ", f);
+    std::fputs("    invalid descriptor: ", f);
     compDesc.Dump(f);
   }
   const Descriptor &specialDesc{special()};
@@ -255,7 +255,7 @@
   } else if (genre_ == Genre::Automatic) {
     std::fputs("    Automatic  ", f);
   } else {
-    std::fprintf(f, "    (bad genre 0x%x)", static_cast<int>(genre_));
+    std::fprintf(f, "    (invalid genre 0x%x)", static_cast<int>(genre_));
   }
   std::fprintf(f, " category %d  kind %d  rank %d  offset 0x%zx\n", category_,
       kind_, rank_, static_cast<std::size_t>(offset_));
diff --git a/flang/runtime/unit.cpp b/flang/runtime/unit.cpp
--- a/flang/runtime/unit.cpp
+++ b/flang/runtime/unit.cpp
@@ -48,7 +48,7 @@
     int unit, const Terminator &terminator) {
   ExternalFileUnit *file{LookUp(unit)};
   if (!file) {
-    terminator.Crash("Not an open I/O unit number: %d", unit);
+    terminator.Crash("%d is not an open I/O unit number", unit);
   }
   return *file;
 }
@@ -855,7 +855,8 @@
   if (access == Access::Direct) {
     RUNTIME_CHECK(handler, openRecl);
     if (!directAccessRecWasSet_) {
-      handler.SignalError("No REC= was specified for a data transfer with ACCESS='DIRECT'");
+      handler.SignalError(
+          "No REC= was specified for a data transfer with ACCESS='DIRECT'");
       return false;
     }
   }
diff --git a/flang/unittests/Runtime/ListInputTest.cpp b/flang/unittests/Runtime/ListInputTest.cpp
--- a/flang/unittests/Runtime/ListInputTest.cpp
+++ b/flang/unittests/Runtime/ListInputTest.cpp
@@ -127,7 +127,7 @@
 
   // Perform failing InputInteger
   ASSERT_DEATH(IONAME(InputInteger)(cookie, dummy),
-      "Bad character 'g' in INTEGER input field");
+      "Invalid character 'g' in INTEGER input field");
 }
 
 // Same test as _TestListInputInvalidFormatWithSingleSuccess_, however no
@@ -148,7 +148,7 @@
 
   // Perform failing InputInteger
   ASSERT_DEATH(IONAME(InputInteger)(cookie, dummy),
-      "Bad character 'g' in INTEGER input field");
+      "Invalid character 'g' in INTEGER input field");
 }
 
 using ParamTy = std::tuple<std::string, std::vector<int>>;