forked from Imagelibrary/binutils-gdb
25e5c20918
The test-case gdb.base/store.exp fails with gcc 7.4.0:
...
nr of unexpected failures 27
...
The first FAIL:
...
110 l = add_float (l, r);
(gdb) PASS: gdb.base/store.exp: continue to wack_float
print l
$21 = <optimized out>
FAIL: gdb.base/store.exp: var float l; print old l, expecting -1
...
relates to this bit in the test-case (compiled at -O0):
...
106 float
107 wack_float (register float u, register float v)
108 {
109 register float l = u, r = v;
110 l = add_float (l, r);
111 return l + r;
112 }
...
and it expects to be able to read and modify variable l before executing line
110, but it already fails to read the value, because l has no DW_AT_location
attribute in the debug info.
Variable l is declared with the register keyword, and GCC implements the
register keyword at -O0 like so:
...
the compiler allocates distinct stack memory for all variables that do not
have the register storage-class specifier; if register is specified, the
variable may have a shorter lifespan than the code would indicate and may
never be placed in memory.
...
The fact that l has no DW_AT_location attribute, matches with the documented
"variable may have a shorter lifespan that code would indicate", (though it
is the most extreme case of it) so the gcc behaviour is valid. We can of
course improve gcc to generate better debuginfo (filed gcc PR91611), but
this not a wrong-debug problem.
[ The test-case passes with gcc 4.2.1, but for the failing test discussed
above, it passes simply because it doesn't store l in a register. ]
With the debug info missing for l, reading and setting l is unsupported, so
fix the FAIL by marking the test UNSUPPORTED instead.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2019-09-12 Tom de Vries <tdevries@suse.de>
* gdb.base/store.exp: Allow register variables to be optimized out at
-O0.
223 lines
6.4 KiB
Plaintext
223 lines
6.4 KiB
Plaintext
# This testcase is part of GDB, the GNU debugger.
|
|
|
|
# Copyright 2002-2019 Free Software Foundation, Inc.
|
|
|
|
# This program is free software; you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation; either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
standard_testfile
|
|
set executable $testfile
|
|
|
|
if { [prepare_for_testing "failed to prepare" $executable $srcfile] } {
|
|
return -1
|
|
}
|
|
|
|
if [get_compiler_info] {
|
|
return -1
|
|
}
|
|
|
|
#
|
|
# set it up at a breakpoint so we can play with the variable values
|
|
#
|
|
|
|
if ![runto_main] then {
|
|
perror "couldn't run to breakpoint"
|
|
continue
|
|
}
|
|
|
|
#
|
|
|
|
proc check_set { t l r new add } {
|
|
global gdb_prompt
|
|
|
|
set prefix "var ${t} l"
|
|
gdb_test "tbreak wack_${t}"
|
|
|
|
set test "continue to wack_${t}"
|
|
gdb_test_multiple "continue" $test {
|
|
-re "register ${t} l = u, r = v;\r\n$gdb_prompt $" {
|
|
# See GCC PR debug/53948.
|
|
send_gdb "next\n"
|
|
exp_continue
|
|
}
|
|
-re "l = add_${t} .l, r.;\r\n$gdb_prompt $" {
|
|
pass $test
|
|
}
|
|
}
|
|
|
|
set supported 1
|
|
set test "${prefix}; print old l, expecting ${l}"
|
|
gdb_test_multiple "print l" "$test" {
|
|
-re " = <optimized out>\r\n$gdb_prompt $" {
|
|
unsupported $test
|
|
set supported 0
|
|
}
|
|
-re " = ${l}\r\n$gdb_prompt $" {
|
|
pass $test
|
|
}
|
|
}
|
|
if { $supported } {
|
|
gdb_test "print r" " = ${r}" \
|
|
"${prefix}; print old r, expecting ${r}"
|
|
gdb_test_no_output "set variable l = 4" \
|
|
"${prefix}; setting l to 4"
|
|
gdb_test "print l" " = ${new}" \
|
|
"${prefix}; print new l, expecting ${new}"
|
|
gdb_test "next" "return l \\+ r;" \
|
|
"${prefix}; next over add call"
|
|
gdb_test "print l" " = ${add}" \
|
|
"${prefix}; print incremented l, expecting ${add}"
|
|
}
|
|
}
|
|
|
|
check_set "charest" "-1 .*" "-2 .*" "4 ..004." "2 ..002."
|
|
check_set "short" "-1" "-2" "4" "2"
|
|
check_set "int" "-1" "-2" "4" "2"
|
|
check_set "long" "-1" "-2" "4" "2"
|
|
check_set "longest" "-1" "-2" "4" "2"
|
|
check_set "float" "-1" "-2" "4" "2"
|
|
check_set "double" "-1" "-2" "4" "2"
|
|
check_set "doublest" "-1" "-2" "4" "2"
|
|
|
|
#
|
|
|
|
proc up_set { t l r new } {
|
|
global gdb_prompt
|
|
|
|
set prefix "upvar ${t} l"
|
|
gdb_test "tbreak add_${t}"
|
|
gdb_test "continue" "return u . v;" \
|
|
"continue to add_${t}"
|
|
gdb_test "up" "l = add_${t} .l, r.;" \
|
|
"${prefix}; up"
|
|
|
|
set supported 1
|
|
set test "${prefix}; print old l, expecting ${l}"
|
|
gdb_test_multiple "print l" "$test" {
|
|
-re " = <optimized out>\r\n$gdb_prompt $" {
|
|
unsupported $test
|
|
set supported 0
|
|
}
|
|
-re " = ${l}\r\n$gdb_prompt $" {
|
|
pass $test
|
|
}
|
|
}
|
|
if { $supported } {
|
|
gdb_test "print r" " = ${r}" \
|
|
"${prefix}; print old r, expecting ${r}"
|
|
gdb_test_no_output "set variable l = 4" \
|
|
"${prefix}; set l to 4"
|
|
gdb_test "print l" " = ${new}" \
|
|
"${prefix}; print new l, expecting ${new}"
|
|
}
|
|
}
|
|
|
|
up_set "charest" "-1 .*" "-2 .*" "4 ..004."
|
|
up_set "short" "-1" "-2" "4"
|
|
up_set "int" "-1" "-2" "4"
|
|
up_set "long" "-1" "-2" "4"
|
|
up_set "longest" "-1" "-2" "4"
|
|
up_set "float" "-1" "-2" "4"
|
|
up_set "double" "-1" "-2" "4"
|
|
up_set "doublest" "-1" "-2" "4"
|
|
|
|
#
|
|
|
|
proc check_struct { t old new } {
|
|
set prefix "var struct ${t} u"
|
|
gdb_test "tbreak wack_struct_${t}"
|
|
gdb_test "continue" "int i; register struct s_${t} u = z_${t};" \
|
|
"continue to wack_struct_${t}"
|
|
gdb_test "next 2" "add_struct_${t} .u.;" \
|
|
"${prefix}; next to add_struct_${t} call"
|
|
gdb_test "print u" " = ${old}" \
|
|
"${prefix}; print old u, expecting ${old}"
|
|
gdb_test_no_output "set variable u = s_${t}" \
|
|
"${prefix}; set u to s_${t}"
|
|
gdb_test "print u" " = ${new}" \
|
|
"${prefix}; print new u, expecting ${new}"
|
|
}
|
|
|
|
check_struct "1" "{s = \\{0}}" "{s = \\{1}}"
|
|
check_struct "2" "{s = \\{0, 0}}" "{s = \\{1, 2}}"
|
|
check_struct "3" "{s = \\{0, 0, 0}}" "{s = \\{1, 2, 3}}"
|
|
check_struct "4" "{s = \\{0, 0, 0, 0}}" "{s = \\{1, 2, 3, 4}}"
|
|
|
|
proc up_struct { t old new } {
|
|
set prefix "up struct ${t} u"
|
|
gdb_test "tbreak add_struct_${t}"
|
|
gdb_test "continue" "for .i = 0; i < sizeof .s. / sizeof .s.s.0..; i..." \
|
|
"continue to add_struct_${t}"
|
|
gdb_test "up" "u = add_struct_${t} .u.;" \
|
|
"${prefix}; up"
|
|
gdb_test "print u" " = ${old}" \
|
|
"${prefix}; print old u, expecting ${old}"
|
|
gdb_test_no_output "set variable u = s_${t}" \
|
|
"${prefix}; set u to s_${t}"
|
|
gdb_test "print u" " = ${new}" \
|
|
"${prefix}; print new u, expecting ${new}"
|
|
}
|
|
|
|
up_struct "1" "{s = \\{0}}" "{s = \\{1}}"
|
|
up_struct "2" "{s = \\{0, 0}}" "{s = \\{1, 2}}"
|
|
up_struct "3" "{s = \\{0, 0, 0}}" "{s = \\{1, 2, 3}}"
|
|
up_struct "4" "{s = \\{0, 0, 0, 0}}" "{s = \\{1, 2, 3, 4}}"
|
|
|
|
#
|
|
|
|
proc check_field { t } {
|
|
global gdb_prompt
|
|
gdb_test "tbreak wack_field_${t}"
|
|
gdb_test "continue" "register struct f_${t} u = f_${t};" \
|
|
"continue field ${t}"
|
|
|
|
# Match either the return statement, or the line immediatly after
|
|
# it. The compiler can end up merging the return statement into
|
|
# the return instruction.
|
|
gdb_test "next" "(return u;|\})" "next field ${t}"
|
|
|
|
gdb_test "print u" " = {i = 1, j = 1, k = 1}" "old field ${t}"
|
|
gdb_test_no_output "set variable u = F_${t}"
|
|
gdb_test "print u" " = {i = 0, j = 0, k = 0}" "new field ${t}"
|
|
|
|
gdb_test_no_output "set variable u = F_${t}, u.i = f_${t}.i"
|
|
gdb_test "print u" " = {i = 1, j = 0, k = 0}" "f_${t}.i"
|
|
|
|
gdb_test_no_output "set variable u = F_${t}, u.j = f_${t}.j"
|
|
gdb_test "print u" " = {i = 0, j = 1, k = 0}" "f_${t}.j"
|
|
|
|
gdb_test_no_output "set variable u = F_${t}, u.k = f_${t}.k"
|
|
gdb_test "print u" " = {i = 0, j = 0, k = 1}" "f_${t}.k"
|
|
|
|
gdb_test_no_output "set variable u = f_${t}, u.i = F_${t}.i"
|
|
gdb_test "print u" " = {i = 0, j = 1, k = 1}" "F_${t}.i"
|
|
|
|
gdb_test_no_output "set variable u = f_${t}, u.j = F_${t}.j"
|
|
gdb_test "print u" " = {i = 1, j = 0, k = 1}" "F_${t}.j"
|
|
|
|
gdb_test_no_output "set variable u = f_${t}, u.k = F_${t}.k"
|
|
gdb_test "print u" " = {i = 1, j = 1, k = 0}" "F_${t}.k"
|
|
|
|
}
|
|
|
|
check_field 1
|
|
check_field 2
|
|
check_field 3
|
|
check_field 4
|
|
|
|
#
|
|
|
|
# WANTED: A fairly portable way of convincing the compiler to split a
|
|
# value across memory and registers.
|
|
|