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[binutils-gdb] Fortran: allocate()d memory is uninitialized
- From: Jan Kratochvil <jkratoch at sourceware dot org>
- To: gdb-cvs at sourceware dot org
- Date: 4 Nov 2015 14:54:08 -0000
- Subject: [binutils-gdb] Fortran: allocate()d memory is uninitialized
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=6f2f1a3a706e56b3fddd7ab1fc9a313343c85d4a
commit 6f2f1a3a706e56b3fddd7ab1fc9a313343c85d4a
Author: Jan Kratochvil <jan.kratochvil@redhat.com>
Date: Wed Nov 4 15:52:41 2015 +0100
Fortran: allocate()d memory is uninitialized
allocate (vla1 (5)) ! vla1-not-allocated
l = allocated(vla1) ! vla1-allocated <------------------
Expecting: ^(510-data-evaluate-expression vla1[^M
]+)?(510\^done,value="\(0, 0, 0, 0, 0\)"[^M
]+[(]gdb[)] ^M
[ ]*)
510-data-evaluate-expression vla1^M
510^done,value="(1.82987403e-09, 7.8472714e-44, 1.82987403e-09, 7.8472714e-44, 2.67929926e+20)"^M
(gdb) ^M
FAIL: gdb.mi/mi-vla-fortran.exp: evaluate allocated vla
gcc-4.9.2-6.fc21.x86_64
I think some older gfortran did initialize allocated memory but that is an
unspecified behavior. I haven't found any initialization mentioned
in Fortran 90 standard (draft) and it is also clearly stated here:
https://software.intel.com/en-us/forums/intel-fortran-compiler-for-linux-and-mac-os-x/topic/268786
Initialization to 0 of allocated arrays (of integers) is an
implementation issue. i.e. do not rely on it.
Joel Brobecker wrote:
I am wondering if it might be better to just relax instead the regexp to allow
any number rather than just remove the test altogether. The test allows us to
verify that, as soon as we're past the "allocate" call, we no longer say "not
allocated".
gdb/testsuite/ChangeLog
2015-11-03 Jan Kratochvil <jan.kratochvil@redhat.com>
Joel Brobecker <brobecker@adacore.com>
* gdb.mi/mi-vla-fortran.exp (evaluate allocated vla): Permit any data.
Diff:
---
gdb/testsuite/ChangeLog | 5 +++++
gdb/testsuite/gdb.mi/mi-vla-fortran.exp | 2 +-
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 6d70c76..3476c86 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-11-03 Jan Kratochvil <jan.kratochvil@redhat.com>
+ Joel Brobecker <brobecker@adacore.com>
+
+ * gdb.mi/mi-vla-fortran.exp (evaluate allocated vla): Permit any data.
+
2015-11-04 Marcin KoÅ?cielnicki <koriakin@0x04.net>
* gdb.reverse/s390-mvcle.c: New test.
diff --git a/gdb/testsuite/gdb.mi/mi-vla-fortran.exp b/gdb/testsuite/gdb.mi/mi-vla-fortran.exp
index d191623..8902ecb 100644
--- a/gdb/testsuite/gdb.mi/mi-vla-fortran.exp
+++ b/gdb/testsuite/gdb.mi/mi-vla-fortran.exp
@@ -69,7 +69,7 @@ mi_run_cmd
mi_expect_stop "breakpoint-hit" "vla" "" ".*vla.f90" "$bp_lineno" \
{ "" "disp=\"del\"" } "run to breakpoint at line $bp_lineno"
mi_gdb_test "510-data-evaluate-expression vla1" \
- "510\\^done,value=\"\\(0, 0, 0, 0, 0\\)\"" "evaluate allocated vla"
+ "510\\^done,value=\"\\(.*\\)\"" "evaluate allocated vla"
mi_create_varobj_checked vla1_allocated vla1 "real\\\(kind=4\\\) \\\(5\\\)" \
"create local variable vla1_allocated"