[Bug fortran/32386] New: Pure function not allowed in specification expression

["john dot harper at vuw dot ac dot nz" <gcc-bugzilla at gcc dot gnu dot org>]

The following program seems to me to be valid Fortran 95, because the f95
standard 5.1.1.5 and 7.1.6.2 say a CHARACTER(n) declaration is OK if n is a
scalar integer restricted expression, in which each primary is a constant,
the intrinsic LEN is allowed, and so are pure functions that are not intrinsic,
not internal, not statement functions, do not have dummy procedure arguments,
and are not recursive. But gfortran won't compile it. Evidence: 

harper@RHEL5 test system: ~/Jfh/Test 52 >cat testspec.f90
MODULE halvestring ! Can halfit be in a specification expression?
CONTAINS
  PURE FUNCTION halfit(s1) RESULT (s2)
    CHARACTER(*),INTENT(IN):: s1
    CHARACTER(len(s1)/2) :: s2
    s2 = s1
  END FUNCTION halfit
END MODULE halvestring
! -----------
PROGRAM testspec
USE  halvestring
CHARACTER(*),PARAMETER :: stringa = 'abcdeedcba'
CHARACTER(len(halfit(stringa))) :: stringb

stringb = halfit(stringa)
PRINT "(I4,A)", len(stringb),' "'//stringb//'"' !   5 "abcde"
END PROGRAM testspec

harper@RHEL5 test system: ~/Jfh/Test 53 >gfortran -v testspec.f90
Driving: gfortran -v testspec.f90 -lgfortranbegin -lgfortran -lm -shared-libgcc
Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-libgcj-multifile
--enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk
--disable-dssi --enable-plugin
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --with-cpu=generic
--host=i386-redhat-linux
Thread model: posix
gcc version 4.1.1 20070105 (Red Hat 4.1.1-52)
 /usr/libexec/gcc/i386-redhat-linux/4.1.1/f951 testspec.f90 -quiet -dumpbase
testspec.f90 -mtune=generic -auxbase testspec -version -I
/usr/lib/gcc/i386-redhat-linux/4.1.1/finclude -o /tmp/ccUf0R9I.s
GNU F95 version 4.1.1 20070105 (Red Hat 4.1.1-52) (i386-redhat-linux)
        compiled by GNU C version 4.1.1 20070105 (Red Hat 4.1.1-52).
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
 In file testspec.f90:13

CHARACTER(len(halfit(stringa))) :: stringb
                                         1
Error: 'stringb' at (1) must have constant character length in this context
harper@RHEL5 test system: ~/Jfh/Test 54 >


-- 
           Summary: Pure function not allowed in specification expression
           Product: gcc
           Version: 4.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: john dot harper at vuw dot ac dot nz
 GCC build triplet: ?
  GCC host triplet: ?
GCC target triplet: i386-redhat-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32386