re PR fortran/64120 ([F03] Wrong handling of allocatable character string)

2018-09-17  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/64120
	* trans-decl.c (gfc_get_symbol_decl): Flag allocatable, scalar
	characters with a variable length expression for deferred init.
	(gfc_trans_deferred_vars): Perform the assignment for these
	symbols by calling gfc_conv_string_length.

2018-09-17  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/64120
	* gfortran.dg/allocatable_scalar_14.f90 : New test.

From-SVN: r264365

gcc/fortran/ChangeLog

 2018-09-17  Paul Thomas  <pault@gcc.gnu.org>
 
+	PR fortran/64120
+	* trans-decl.c (gfc_get_symbol_decl): Flag allocatable, scalar
+	characters with a variable length expression for deferred init.
+	(gfc_trans_deferred_vars): Perform the assignment for these
+	symbols by calling gfc_conv_string_length.
+
+2018-09-17  Paul Thomas  <pault@gcc.gnu.org>
+
 	PR fortran/85954
 	* resolve.c (resolve_assoc_var): If the target expression is a
 	deferred charlen dummy and the associate name shares the

gcc/fortran/trans-decl.c

@@ -1745,6 +1745,13 @@ gfc_get_symbol_decl (gfc_symbol * sym)
 	  && !(sym->attr.use_assoc && !intrinsic_array_parameter)))
     gfc_defer_symbol_init (sym);
 
+  if (sym->ts.type == BT_CHARACTER
+      && sym->attr.allocatable
+      && !sym->attr.dimension
+      && sym->ts.u.cl && sym->ts.u.cl->length
+      && sym->ts.u.cl->length->expr_type == EXPR_VARIABLE)
+    gfc_defer_symbol_init (sym);
+
   /* Associate names can use the hidden string length variable
      of their associated target.  */
   if (sym->ts.type == BT_CHARACTER
@@ -4603,6 +4610,13 @@ gfc_trans_deferred_vars (gfc_symbol * proc_sym, gfc_wrapped_block * block)
 	      gfc_set_backend_locus (&sym->declared_at);
 	      gfc_start_block (&init);
 
+	      if (sym->ts.type == BT_CHARACTER
+		  && sym->attr.allocatable
+		  && !sym->attr.dimension
+		  && sym->ts.u.cl && sym->ts.u.cl->length
+		  && sym->ts.u.cl->length->expr_type == EXPR_VARIABLE)
+		gfc_conv_string_length (sym->ts.u.cl, NULL, &init);
+
 	      if (!sym->attr.pointer)
 		{
 		  /* Nullify and automatic deallocation of allocatable

gcc/testsuite/ChangeLog

+2018-09-17  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/64120
+	* gfortran.dg/allocatable_scalar_14.f90 : New test.
+
 2018-09-17  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/87301

gcc/testsuite/gfortran.dg/allocatable_scalar_14.f90

+! { dg-do run }
+!
+! Test the fix for PR64120 in which the initialisation of the
+! string length of 's' was not being done.
+!
+! Contributed by Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
+!
+   call g(1)
+   call g(2)
+contains
+  subroutine g(x)
+      integer :: x
+      character(len=x), allocatable :: s
+      allocate(s)
+      if (len(s) .ne. x) stop x
+  end subroutine
+end