testsuite, fortran: make mixed-lang-stack less compiler dependent

In the gdb.fortran/mixed-lang-stack.exp test when somewhere deep in a
bunch of nested function calls we issue and test a 'info args' command
for the mixed_func_1b function (when in that function's frame).

The signature of the function looks like

  subroutine mixed_func_1b(a, b, c, d, e, g)
    use type_module
    implicit none

    integer :: a
    real(kind=4) :: b
    real(kind=8) :: c
    complex(kind=4) :: d
    character(len=*) :: e
    character(len=:), allocatable :: f
    TYPE(MyType) :: g

and usually one would expect arguments a, b, c, d, e, and g to be
emitted here.  However, due to some compiler dependent treatment of the
e array the actual output in the test (with gfortran/ifx) is

  (gdb) info args
  a = 1
  b = 2
  c = 3
  d = (4,5)
  e = 'abcdef'
  g = ( a = 1.5, b = 2.5 )
  _e = 6

where the compiler generated '_e' is emitted as the length of e.  While
ifort also generates an additional length argument, the naming (which is
up to the compilers here I think, I could not find anything in the
Fortran standard about this) is different and we see

  (gdb) info args
  a = 1
  b = 2
  c = 3
  d = (4,5)
  e = 'abcdef'
  g = ( a = 1.5, b = 2.5 )
  .tmp.E.len_V$4a = 6

To make both outputs pass the test, I kept the additional argument for now and
made the regex for the emitted name of the last variable match any
arbitrary name.

Approved-by: Tom Tromey <tom@tromey.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/gdb/testsuite/gdb.fortran/mixed-lang-stack.exp b/gdb/testsuite/gdb.fortran/mixed-lang-stack.exp
index 3973f68..20983d6 100644
--- a/gdb/testsuite/gdb.fortran/mixed-lang-stack.exp
+++ b/gdb/testsuite/gdb.fortran/mixed-lang-stack.exp
@@ -181,6 +181,13 @@ proc run_tests { lang } {
 	    set g_val_pattern "\\( a = 1.5, b = 2.5 \\)"
 	}
 
+	# The last argument here in info args is compiler generated.  It
+	# contains length of the passed array e (we are in mixed_func_1b here).
+	# For gfortran and ifx the compilers conveniently named this '_e',
+	# ifort however prints .tmp.E.len_V$4a.  As is seems unreasonable to
+	# test for an artificially created name and as at the same time all
+	# 3 tested compilers emit this argument, we only check for its
+	# existence and its value (6).
 	set args_pattern [multi_line \
 			      "a = 1" \
 			      "b = 2" \
@@ -188,7 +195,7 @@ proc run_tests { lang } {
 			      "d = ${d_pattern}" \
 			      "e = ${e_pattern}" \
 			      "g = ${g_val_pattern}" \
-			      "_e = 6" ]
+			      ".* = 6" ]
 
 	gdb_test "info args" $args_pattern \
 	    "info args in frame #7"