[flang] Correct a typo when parsing format token white space

[vdonaldson]

Summary

A format such as "( D C, X6. 2 )" is parsed the same as "(DC,X6.2)".

[vdonaldson]

linux -> windows transfers are not currently working, so the diffs are a simple cut+paste. There are no actual differences, including white space, on format.h line 152 and io07.f90 lines 6-7.

[vdonaldson]

https://reviews.llvm.org/D122763

flang/include/flang/Common/format.h

private:
   char argString_[3]{}; // 1-2 character msg arg; usually edit descriptor name
   bool formatHasErrors_{false};
   bool unterminatedFormatError_{false};
   bool suppressMessageCascade_{false};
   bool reporterExit_{false};
   int maxNesting_{0}; // max level of nested parentheses
 };
 
-template <typename CHAR> static inline bool IsWhite(CHAR c) {
+template <typename CHAR> static inline bool IsWhite(CHAR c) {
   // White space.  ' ' is standard.  Other characters are extensions.
   // Extension candidates:
   //   '\t' (horizontal tab)
   //   '\n' (new line)
   //   '\v' (vertical tab)
   //   '\f' (form feed)
   //   '\r' (carriage ret)
   return c == ' ' || c == '\t' || c == '\v';
 }
 
 template <typename CHAR> CHAR FormatValidator<CHAR>::NextChar() {
   for (++cursor_; cursor_ < end_; ++cursor_) {
     if (!IsWhite(*cursor_)) {
       return toupper(*cursor_);
     }
   }
   cursor_ = end_; // don't allow cursor_ > end_
   return ' ';
 }
 
 template <typename CHAR> CHAR FormatValidator<CHAR>::LookAheadChar() {
   for (laCursor_ = cursor_ + 1; laCursor_ < end_; ++laCursor_) {
-    if (!IsWhite(*cursor_)) {
+    if (!IsWhite(*laCursor_)) {
       return toupper(*laCursor_);
     }
   }
   laCursor_ = end_; // don't allow laCursor_ > end_
   return ' ';
 }
 
 // After a call to LookAheadChar, set token kind and advance cursor to laCursor.

flang/test/Semantics/io07.f90

 ! RUN: %python %S/test_errors.py %s %flang_fc1
 1001 format(A)
 
      !ERROR: Format statement must be labeled
      format(A)
-
-2001 format(3I8, 3Z8)
-2002 format(3I8, Z8)
-2003 format(  3  I  8  ,  3  Z  8  )
+
+2001 format(3I8, 3Z8)
+2002 format(DC, F8.2, 3I8, Z8)
+2003 format(  D C , F 8 . 2 , 3  I  8  ,  3  Z  8  )
 2004 format(20PF10.2)
 2005 format(20P,F10.2)
 2006 format(20P7F10.2)
 2007 format(1X/)
 2008 format(/02x)
 2009 format(1x/02x)
 2010 format(2L2:)
 2011 format(:2L2)

 3103 format(5X, 'abc', *((:)))
 
 4001 format(2(X))
 
      !ERROR: List repeat specifier must be positive
      !ERROR: 'DT' edit descriptor repeat specifier must be positive
 4101 format(0(X), 0dt)
 
 6001 format(((I0, B0)))
      !ERROR: 'A' edit descriptor 'w' value must be positive
      !ERROR: 'L' edit descriptor 'w' value must be positive
 6101 format((A0), ((L0)))
 
      !ERROR: 'L' edit descriptor 'w' value must be positive
 6102 format((3(((L 0 0 0)))))
 
 7001 format(17G8.1, 17G8.1e3)