With target board unix/-m32, I run into:
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FAIL: gdb.fortran/lbound-ubound.exp: test 12: check value of lbound ('array_1d_4bytes_overflow') expression
FAIL: gdb.fortran/lbound-ubound.exp: test 12: check value of ubound ('array_1d_4bytes_overflow') expression
FAIL: gdb.fortran/lbound-ubound.exp: test 12: lbounds match
FAIL: gdb.fortran/lbound-ubound.exp: test 12: ubounds match
FAIL: gdb.fortran/lbound-ubound.exp: p lbound(array_1d_4bytes_overflow, 1, 8)
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In more detail:
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(gdb) p lbound (array_1d_4bytes_overflow)^M
$71 = (2147483644)^M
(gdb) FAIL: gdb.fortran/lbound-ubound.exp: test 12: check value of lbound ('array_1d_4bytes_overflow') expression
p ubound (array_1d_4bytes_overflow)^M
$72 = (-2147483637)^M
(gdb) FAIL: gdb.fortran/lbound-ubound.exp: test 12: check value of ubound ('array_1d_4bytes_overflow') expression
...

With native instead I get:
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(gdb) p lbound (array_1d_4bytes_overflow)^M
$71 = (2147483644)^M
(gdb) PASS: gdb.fortran/lbound-ubound.exp: test 12: check value of lbound ('array_1d_4bytes_overflow') expression
p ubound (array_1d_4bytes_overflow)^M
$72 = (-2147483637)^M
(gdb) PASS: gdb.fortran/lbound-ubound.exp: test 12: check value of ubound ('array_1d_4bytes_overflow') expression
...

Hmm, that's the same output, so the difference is in the expected value.  Let's annotate that in the test name:
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diff --git a/gdb/testsuite/gdb.fortran/lbound-ubound.exp b/gdb/testsuite/gdb.fortran/lbound
-ubound.exp
index 334713666e0..f4093092a11 100644
--- a/gdb/testsuite/gdb.fortran/lbound-ubound.exp
+++ b/gdb/testsuite/gdb.fortran/lbound-ubound.exp
@@ -137,10 +137,10 @@ while { $test_count < 500 } {
        # lower bounds for an array.
        set pattern [string_to_regexp " = $expected_lbound"]
        gdb_test "p lbound ($array_name)" "$pattern" \
-           "check value of lbound ('$array_name') expression"
+           "check value of lbound ('$array_name') expression, expected: $expected_lbound"

        set pattern [string_to_regexp " = $expected_ubound"]
        gdb_test "p ubound ($array_name)" "$pattern" \
-           "check value of ubound ('$array_name') expression"
+           "check value of ubound ('$array_name') expression, expected: $expected_ubound"

 
        # Now ask for each bound in turn and check it against the
        # expected results.
...

That's a mismatch indeed:
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(gdb) p lbound (array_1d_4bytes_overflow)^M
$71 = (2147483644)^M
(gdb) FAIL: gdb.fortran/lbound-ubound.exp: test 12: check value of lbound ('array_1d_4bytes_overflow') expression, expected: (1)
p ubound (array_1d_4bytes_overflow)^M
$72 = (-2147483637)^M
(gdb) FAIL: gdb.fortran/lbound-ubound.exp: test 12: check value of ubound ('array_1d_4bytes_overflow') expression, expected: (0)
...