testsuite: Fix false Fortran regressions with recent gcc

gcc-4.9.2-6.fc21.x86_64 -> gcc-5.3.1-2.fc23.x86_64

-PASS: gdb.fortran/vla-ptype.exp: ptype pvla not initialized
+FAIL: gdb.fortran/vla-ptype.exp: ptype pvla not initialized
-PASS: gdb.fortran/vla-history.exp: print vla1 allocated
+FAIL: gdb.fortran/vla-history.exp: print vla1 allocated
-PASS: gdb.fortran/vla-history.exp: print $2
+FAIL: gdb.fortran/vla-history.exp: print $2
-PASS: gdb.fortran/vla-value.exp: print undefined pvla
+FAIL: gdb.fortran/vla-value.exp: print undefined pvla
-PASS: gdb.fortran/vla-value.exp: print non-associated &pvla
+FAIL: gdb.fortran/vla-value.exp: print non-associated &pvla
-PASS: gdb.fortran/vla-value.exp: print undefined pvla(1,3,8)
+FAIL: gdb.fortran/vla-value.exp: print undefined pvla(1,3,8)

These issues get fixed (or removed if no longer applicable) by attached patch.

It is based on Googled:
	http://www.cs.rpi.edu/~szymansk/OOF90/bugs.html#5
	When a pointer is declared its status is undefined, and cannot be
	safely queried with the associated intrinsic.
	-> nullify(VARNAME)
+
	https://software.intel.com/en-us/forums/intel-fortran-compiler-for-linux-and-mac-os-x/topic/268786
	ALLOCATE is not supposed to initialize the array.
	-> Remove checks like an initial print is: \\( *0, *0, *0...\\)

These regressions remain:
	-PASS: gdb.fortran/library-module.exp: print var_i in lib
	+FAIL: gdb.fortran/library-module.exp: print var_i in lib
	-PASS: gdb.fortran/library-module.exp: print var_i in main
	+FAIL: gdb.fortran/library-module.exp: print var_i in main
I believe it is more a GDB bug (in a code contributed by me), filed:
	gdb.fortran/library-module.exp false regression on GCC upgrade
	https://sourceware.org/bugzilla/show_bug.cgi?id=19635

gdb/testsuite/ChangeLog
2016-02-14  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix compatibility with recent gfortran-5.3.1.
	* gdb.fortran/vla-history.exp (print vla1 allocated)
	(print vla2 allocated, print $2, print $3): Remove
	(print $4): Rename to ...
	(print $2): ... here.
	(print $9): Rename to ...
	(print $5): ... here.
	(print $10): Rename to ...
	(print $6): ... here.
	* gdb.fortran/vla.f90: Add pvla initialization.

3 files changed, 18 insertions, 12 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 247173d..a44cba2 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,18 @@
 2016-02-14  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
+	Fix compatibility with recent gfortran-5.3.1.
+	* gdb.fortran/vla-history.exp (print vla1 allocated)
+	(print vla2 allocated, print $2, print $3): Remove
+	(print $4): Rename to ...
+	(print $2): ... here.
+	(print $9): Rename to ...
+	(print $5): ... here.
+	(print $10): Rename to ...
+	(print $6): ... here.
+	* gdb.fortran/vla.f90: Add pvla initialization.
+
+2016-02-14  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
 	* gdb.fortran/vla-value-sub-finish.exp (set max-value-size 1024*1024):
 	New test.
 	* gdb.fortran/vla-value-sub.exp: Likewise.
diff --git a/gdb/testsuite/gdb.fortran/vla-history.exp b/gdb/testsuite/gdb.fortran/vla-history.exp
index 315c61a..1478e6b 100644
--- a/gdb/testsuite/gdb.fortran/vla-history.exp
+++ b/gdb/testsuite/gdb.fortran/vla-history.exp
@@ -32,10 +32,6 @@ gdb_test "print vla1" " = <not allocated>" "print non-allocated vla1"
 
 gdb_breakpoint [gdb_get_line_number "vla2-allocated"]
 gdb_continue_to_breakpoint "vla2-allocated"
-gdb_test "print vla1" " = \\( *\\( *\\( *0, *0, *0,\[()0, .\]*\\)" \
-  "print vla1 allocated"
-gdb_test "print vla2" " = \\( *\\( *\\( *0, *0, *0,\[()0, .\]*\\)" \
-  "print vla2 allocated"
 
 gdb_breakpoint [gdb_get_line_number "vla1-filled"]
 gdb_continue_to_breakpoint "vla1-filled"
@@ -45,12 +41,8 @@ gdb_test "print vla1" \
 
 # Try to access history values for full vla prints.
 gdb_test "print \$1" " = <not allocated>" "print \$1"
-gdb_test "print \$2" " = \\( *\\( *\\( *0, *0, *0,\[()0, .\]*\\)" \
-  "print \$2"
-gdb_test "print \$3" " = \\( *\\( *\\( *0, *0, *0,\[()0, .\]*\\)" \
-  "print \$3"
-gdb_test "print \$4" \
-  " = \\( *\\( *\\( *1311, *1311, *1311,\[()1311, .\]*\\)" "print \$4"
+gdb_test "print \$2" \
+  " = \\( *\\( *\\( *1311, *1311, *1311,\[()1311, .\]*\\)" "print \$2"
 
 gdb_breakpoint [gdb_get_line_number "vla2-filled"]
 gdb_continue_to_breakpoint "vla2-filled"
@@ -58,5 +50,5 @@ gdb_test "print vla2(1,43,20)" " = 1311" "print vla2(1,43,20)"
 gdb_test "print vla1(1,3,8)" " = 1001" "print vla2(1,3,8)"
 
 # Try to access history values for vla values.
-gdb_test "print \$9" " = 1311" "print \$9"
-gdb_test "print \$10" " = 1001" "print \$10"
+gdb_test "print \$5" " = 1311" "print \$5"
+gdb_test "print \$6" " = 1001" "print \$6"
diff --git a/gdb/testsuite/gdb.fortran/vla.f90 b/gdb/testsuite/gdb.fortran/vla.f90
index 6a96635..c76d24c 100644
--- a/gdb/testsuite/gdb.fortran/vla.f90
+++ b/gdb/testsuite/gdb.fortran/vla.f90
@@ -19,6 +19,7 @@ program vla
   real, target, allocatable :: vla3 (:, :)
   real, pointer :: pvla (:, :, :)
   logical :: l
+  nullify(pvla)
 
   allocate (vla1 (10,10,10))          ! vla1-init
   l = allocated(vla1)