Fix various tests to use -no-pie linker flag when needed
Commit Message
Various test use test code written in i386 / x86_64 assembly that cannot
be used to create PIE executables. Therefore compilation of test programs
failed on systems where the compiler default is to create PIE executable.
The solution is to use -no-pie linker flag, however, such flag may not
(is not) supported by all compilers GDB needs to support. To handle this,
introduce a new flag to gdb_compile - nopie - which inserts -no-pie linker
flag where supported and is no-op where it is not. By default, -no-pie flag
is inserted since most modern compiler do support it.
gdb/testsuite/ChangeLog:
2018-08-28 Jan Vrany <jan.vrany@fit.cvut.cz>
* gdb.arch/amd64-disp-step.exp: Use -no-pie linker flag
to enforce non-PIE executable.
* gdb.arch/amd64-entry-value.exp: Likewise.
* gdb.arch/amd64-invalid-stack-middle.exp: Likewise.
* gdb.arch/i386-float.exp: Likewise.
* gdb.arch/i386-signal.exp: Likewise.
* gdb.mi/mi-reg-undefined.exp: Likewise.
---
gdb/testsuite/ChangeLog | 12 ++++++++++++
gdb/testsuite/gdb.arch/amd64-disp-step.exp | 3 ++-
gdb/testsuite/gdb.arch/amd64-entry-value.exp | 2 +-
.../gdb.arch/amd64-invalid-stack-middle.exp | 3 +--
gdb/testsuite/gdb.arch/i386-float.exp | 2 +-
gdb/testsuite/gdb.arch/i386-signal.exp | 2 +-
gdb/testsuite/gdb.mi/mi-reg-undefined.exp | 2 +-
gdb/testsuite/lib/gdb.exp | 13 +++++++++++++
8 files changed, 32 insertions(+), 7 deletions(-)
Comments
On 2018-12-13 10:20, Jan Vrany wrote:
> diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
> index 5a5713b114..f25df0a772 100644
> --- a/gdb/testsuite/lib/gdb.exp
> +++ b/gdb/testsuite/lib/gdb.exp
> @@ -3482,6 +3482,7 @@ set gdb_saved_set_unbuffered_mode_obj ""
> # dynamically load libraries at runtime. For example, on Linux,
> this adds
> # -ldl so that the test can use dlopen.
> # - nowarnings: Inhibit all compiler warnings.
> +# - nopie: Prevent creation of PIE executables.
> #
> # And here are some of the not too obscure options understood by
> DejaGnu that
> # influence the compilation:
> @@ -3603,6 +3604,18 @@ proc gdb_compile {source dest type options} {
> set options [lreplace $options $nowarnings $nowarnings $flag]
> }
>
> + # Replace the "nopie" option with the appropriate additional_flags
> + # to disable PIE executables.
> + set nopie [lsearch -exact $options nopie]
> + if {$nopie != -1} {
> + if [target_info exists gdb,nowarnings_flag] {
s/nowarnings_flag/nopie_flag/
> + set flag "ldflags=[target_info gdb,nopie_flag]"
> + } else {
> + set flag "ldflags=-no-pie"
> + }
> + set options [lreplace $options $nopie $nopie $flag]
> + }
> +
With this, people who run tests against gcc 4.8 will be forced to create
a specific board file to override the nopie_flag, whereas currently it's
possible to do it all from the command line:
$ make check TESTS="gdb.arch/amd64-disp-step.exp"
RUNTESTFLAGS='CC_FOR_TARGET="gcc-4.8"'
One way to avoid that would be to auto-detect whether the toolchain
generates PIE executables by default. If the nopie option is requested
but the toolchain generates non-PIE by default, we would not pass any
additional flags. On Linux, we can generate an executable and use
"readelf -h" to check for the type of ELF artifact generated.
Another way would be to check whether the toolchain knows the -no-pie
flag, and assume that if it doesn't, it's because it probably generates
non-PIE by default, so we don't need to pass anything. That would break
with toolchains that generate PIE by default but use another flag to
disable PIE (I am not aware of any that fits in this category), but
people would still have the possibiliy of overriding it with a board
file.
Or maybe this just fine, and we can require the few people who test
against gcc 4.8 to use a board file.
Simon
@@ -1,3 +1,15 @@
+2018-12-13 Jan Vrany <jan.vrany@fit.cvut.cz>
+
+ * lib/gdb.exp (gdb_compile): Add new nopie flag enforce
+ non-PIE executables.
+ * gdb.arch/amd64-disp-step.exp: Use nopie flag to enforce
+ non-PIE executable.
+ * gdb.arch/amd64-entry-value.exp: Likewise.
+ * gdb.arch/amd64-invalid-stack-middle.exp: Likewise.
+ * gdb.arch/i386-float.exp: Likewise.
+ * gdb.arch/i386-signal.exp: Likewise.
+ * gdb.mi/mi-reg-undefined.exp: Likewise.
+
2018-12-12 Andrew Burgess <andrew.burgess@embecosm.com>
* gdb.base/annota1.exp: Update a test regexp.
@@ -25,9 +25,10 @@ if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
set newline "\[\r\n\]*"
+set opts {debug nopie}
standard_testfile .S
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } {
+if { [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] } {
return -1
}
@@ -14,7 +14,7 @@
# along with this program. If not, see <http://www.gnu.org/licenses/>.
standard_testfile .s
-set opts {}
+set opts {nopie}
if [info exists COMPILE] {
# make check RUNTESTFLAGS="gdb.arch/amd64-entry-value.exp COMPILE=1"
@@ -27,7 +27,6 @@
# run twice, and we restart gdb before testing each different command to
# ensure that nothing is being cached.
-set opts {}
standard_testfile .S
if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
@@ -35,7 +34,7 @@ if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
return
}
-if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile} $opts] } {
+if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile} {nopie}] } {
return -1
}
@@ -28,7 +28,7 @@ standard_testfile .S
# some targets have leading underscores on assembly symbols.
set additional_flags [gdb_target_symbol_prefix_flags_asm]
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile [list debug $additional_flags]] } {
+if { [prepare_for_testing "failed to prepare" $testfile $srcfile [list debug nopie $additional_flags]] } {
return -1
}
@@ -23,7 +23,7 @@ if { ![istarget "i?86-*-*"] && ![istarget "x86_64-*-*"] } then {
standard_testfile
if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
- executable { debug }] != "" } {
+ executable { debug nopie }] != "" } {
untested "failed to compile"
return -1
}
@@ -33,7 +33,7 @@ if [mi_gdb_start] {
standard_testfile .S
-if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug nopie}] != "" } {
untested "failed to compile"
return -1
}
@@ -3482,6 +3482,7 @@ set gdb_saved_set_unbuffered_mode_obj ""
# dynamically load libraries at runtime. For example, on Linux, this adds
# -ldl so that the test can use dlopen.
# - nowarnings: Inhibit all compiler warnings.
+# - nopie: Prevent creation of PIE executables.
#
# And here are some of the not too obscure options understood by DejaGnu that
# influence the compilation:
@@ -3603,6 +3604,18 @@ proc gdb_compile {source dest type options} {
set options [lreplace $options $nowarnings $nowarnings $flag]
}
+ # Replace the "nopie" option with the appropriate additional_flags
+ # to disable PIE executables.
+ set nopie [lsearch -exact $options nopie]
+ if {$nopie != -1} {
+ if [target_info exists gdb,nowarnings_flag] {
+ set flag "ldflags=[target_info gdb,nopie_flag]"
+ } else {
+ set flag "ldflags=-no-pie"
+ }
+ set options [lreplace $options $nopie $nopie $flag]
+ }
+
if { $type == "executable" } {
if { ([istarget "*-*-mingw*"]
|| [istarget "*-*-*djgpp"]