re PR fortran/69423 (Invalid optimization with deferred-length character)

2016-02-20  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/69423
	* trans-decl.c (create_function_arglist): Deferred character
	length functions, with and without declared results, address
	the passed reference type as '.result' and the local string
	length as '..result'.
	(gfc_null_and_pass_deferred_len): Helper function to null and
	return deferred string lengths, as needed.
	(gfc_trans_deferred_vars): Call it, thereby reducing repeated
	code, add call for deferred arrays and reroute pointer function
	results. Avoid using 'tmp' for anything other that a temporary
	tree by introducing 'type_of_array' for the arrayspec type.

2016-02-20  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/69423
	* gfortran.dg/deferred_character_15.f90 : New test.

From-SVN: r233589

gcc/fortran/ChangeLog

+2016-02-20  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/69423
+	* trans-decl.c (create_function_arglist): Deferred character
+	length functions, with and without declared results, address
+	the passed reference type as '.result' and the local string
+	length as '..result'.
+	(gfc_null_and_pass_deferred_len): Helper function to null and
+	return deferred string lengths, as needed.
+	(gfc_trans_deferred_vars): Call it, thereby reducing repeated
+	code, add call for deferred arrays and reroute pointer function
+	results. Avoid using 'tmp' for anything other that a temporary
+	tree by introducing 'type_of_array' for the arrayspec type.
+
 2015-02-16  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/69742

gcc/testsuite/ChangeLog

+2016-02-20  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/69423
+	* gfortran.dg/deferred_character_15.f90 : New test.
+
 2016-02-20  Dominique d'Humieres  <dominiq@lps.ens.fr>
 
 	PR fortran/57365

gcc/testsuite/gfortran.dg/deferred_character_15.f90

+! { dg-do run }
+!
+! Test the fix for PR69423.
+!
+! Contributed by Antony Lewis  <antony@cosmologist.info>
+!
+program tester
+  character(LEN=:), allocatable :: S
+  S= test(2)
+  if (len(S) .ne. 4) call abort
+  if (S .ne. "test") call abort
+  if (allocated (S)) deallocate (S)
+
+  S= test2(2)
+  if (len(S) .ne. 4) call abort
+  if (S .ne. "test") call abort
+  if (allocated (S)) deallocate (S)
+contains
+  function test(alen)
+    character(LEN=:), allocatable :: test
+    integer alen, i
+    do i = alen, 1, -1
+      test = 'test'
+      exit
+    end do
+!       This line would print nothing when compiled with -O1 and higher.
+!       print *, len(test),test
+    if (len(test) .ne. 4) call abort
+    if (test .ne. "test") call abort
+  end function test
+
+  function test2(alen) result (test)
+    character(LEN=:), allocatable :: test
+    integer alen, i
+    do i = alen, 1, -1
+      test = 'test'
+      exit
+    end do
+!       This worked before the fix.
+!       print *, len(test),test
+    if (len(test) .ne. 4) call abort
+    if (test .ne. "test") call abort
+  end function test2
+end program tester