kvm-unit-tests: inconsistent test result between run_tests.sh and standalone test

kvm-unit-tests: inconsistent test result between run_tests.sh and standalone test

[Guoqing Jiang]

Hi,

I find the two test results (pmu and intel_cet) are quite different, but 
other
test results are consistent.

gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh
...
*PASS pmu (142 tests)*
...
*FAIL intel_cet*
...

1. pmu standalone test
gjiang@x1:~/source/kvm-unit-tests/tests> ./pmu
BUILD_HEAD=73d9d850
timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot 
-nodefaults -device pc-testdev -device 
isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device 
pci-testdev -machine accel=kvm -kernel /tmp/tmp.Bai8UEIh2F -smp 1 -cpu 
max # -initrd /tmp/tmp.DFE9VFPOdp
enabling apic
smp: waiting for 0 APs
paging enabled
cr0 = 80010011
cr3 = 1007000
cr4 = 20
PMU version:         2
GP counters:         4
GP counter width:    48
Mask length:         7
Fixed counters:      3
Fixed counter width: 48
PASS: core cycles-0
...
FAIL: llc misses-0
FAIL: llc misses-1
FAIL: llc misses-2
FAIL: llc misses-3
...
SUMMARY: 142 tests, 4 unexpected failures
*FAIL pmu (142 tests, 4 unexpected failures)

*And

gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat
/usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev 
-device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio 
-device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat # -initrd 
/tmp/tmp.jiEHps3KLW
enabling apic
smp: waiting for 0 APs
paging enabled
cr0 = 80010011
cr3 = 1007000
cr4 = 20
*SKIP: No pmu is detected!**
**SUMMARY: 1 tests, 1 skipped*

**
2. intel_cet
gjiang@x1:~/source/kvm-unit-tests/tests> ./intel_cet
BUILD_HEAD=73d9d850
*skip intel_cet (test kernel not present)*

Then I am not sure which test result should be correct, standalone test
or run all tests. Or am I missed something fundamentally?

Thanks for your reply in advance.

Guoqing

Re: kvm-unit-tests: inconsistent test result between run_tests.sh and standalone test

[Andrew Jones]

On Tue, Nov 15, 2022 at 04:11:48PM +0800, Guoqing Jiang wrote:
> Hi,
> 
> I find the two test results (pmu and intel_cet) are quite different, but
> other
> test results are consistent.
> 
> gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh
> ...
> *PASS pmu (142 tests)*
> ...
> *FAIL intel_cet*
> ...
> 
> 1. pmu standalone test
> gjiang@x1:~/source/kvm-unit-tests/tests> ./pmu
> BUILD_HEAD=73d9d850
> timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot
> -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4
> -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel
> /tmp/tmp.Bai8UEIh2F -smp 1 -cpu max # -initrd /tmp/tmp.DFE9VFPOdp
> enabling apic
> smp: waiting for 0 APs
> paging enabled
> cr0 = 80010011
> cr3 = 1007000
> cr4 = 20
> PMU version:         2
> GP counters:         4
> GP counter width:    48
> Mask length:         7
> Fixed counters:      3
> Fixed counter width: 48
> PASS: core cycles-0
> ...
> FAIL: llc misses-0
> FAIL: llc misses-1
> FAIL: llc misses-2
> FAIL: llc misses-3
> ...
> SUMMARY: 142 tests, 4 unexpected failures
> *FAIL pmu (142 tests, 4 unexpected failures)
> 
> *And
> 
> gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat
> /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev
> -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio
> -device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat # -initrd
> /tmp/tmp.jiEHps3KLW
> enabling apic
> smp: waiting for 0 APs
> paging enabled
> cr0 = 80010011
> cr3 = 1007000
> cr4 = 20
> *SKIP: No pmu is detected!**
> **SUMMARY: 1 tests, 1 skipped*
> 

./x86-run doesn't look at x86/unittests.cfg, which is where the pmu test
states that it needs '-cpu max'. You either need to add it yourself, e.g.
'./x86-run ./x86/pmu.flat -cpu max' or use run_tests.sh, e.g.
'./run_tests.sh pmu'. standalone tests get their parameters from
x86/unittests.cfg, which is why it's already using '-cpu max'.

> **
> 2. intel_cet
> gjiang@x1:~/source/kvm-unit-tests/tests> ./intel_cet
> BUILD_HEAD=73d9d850
> *skip intel_cet (test kernel not present)*

This error looks like x86/cet.c wasn't built. Maybe do a 'make clean' and
'make standalone' again and watch that cet.c doesn't fail to compile.

> 
> Then I am not sure which test result should be correct, standalone test
> or run all tests. Or am I missed something fundamentally?
> 
> Thanks for your reply in advance.

Thanks,
drew

Re: kvm-unit-tests: inconsistent test result between run_tests.sh and standalone test

[Guoqing Jiang]

Hi,

Thanks for the quick reply!

On 11/15/22 4:42 PM, Andrew Jones wrote:
> On Tue, Nov 15, 2022 at 04:11:48PM +0800, Guoqing Jiang wrote:
>> Hi,
>>
>> I find the two test results (pmu and intel_cet) are quite different, but
>> other
>> test results are consistent.
>>
>> gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh
>> ...
>> *PASS pmu (142 tests)*
>> ...
>> *FAIL intel_cet*
>> ...
>>
>> 1. pmu standalone test
>> gjiang@x1:~/source/kvm-unit-tests/tests> ./pmu
>> BUILD_HEAD=73d9d850
>> timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot
>> -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4
>> -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel
>> /tmp/tmp.Bai8UEIh2F -smp 1 -cpu max # -initrd /tmp/tmp.DFE9VFPOdp
>> enabling apic
>> smp: waiting for 0 APs
>> paging enabled
>> cr0 = 80010011
>> cr3 = 1007000
>> cr4 = 20
>> PMU version:         2
>> GP counters:         4
>> GP counter width:    48
>> Mask length:         7
>> Fixed counters:      3
>> Fixed counter width: 48
>> PASS: core cycles-0
>> ...
>> FAIL: llc misses-0
>> FAIL: llc misses-1
>> FAIL: llc misses-2
>> FAIL: llc misses-3
>> ...
>> SUMMARY: 142 tests, 4 unexpected failures
>> *FAIL pmu (142 tests, 4 unexpected failures)
>>
>> *And
>>
>> gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat
>> /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev
>> -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio
>> -device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat # -initrd
>> /tmp/tmp.jiEHps3KLW
>> enabling apic
>> smp: waiting for 0 APs
>> paging enabled
>> cr0 = 80010011
>> cr3 = 1007000
>> cr4 = 20
>> *SKIP: No pmu is detected!**
>> **SUMMARY: 1 tests, 1 skipped*
>>
> ./x86-run doesn't look at x86/unittests.cfg, which is where the pmu test
> states that it needs '-cpu max'. You either need to add it yourself, e.g.
> './x86-run ./x86/pmu.flat -cpu max' or use run_tests.sh, e.g.
> './run_tests.sh pmu'. standalone tests get their parameters from
> x86/unittests.cfg, which is why it's already using '-cpu max'.

Thanks for the tips. And I still see two different results, one is PASS
while another has failures.

gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)

gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat -cpu max
/usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev 
-device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio 
-device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat -cpu max # 
-initrd /tmp/tmp.wBVHPW1XUr
enabling apic
smp: waiting for 0 APs
paging enabled
cr0 = 80010011
cr3 = 1007000
cr4 = 20
PMU version:         2
GP counters:         4
GP counter width:    48
Mask length:         7
Fixed counters:      3
Fixed counter width: 48
...
FAIL: llc misses-0
FAIL: llc misses-1
FAIL: llc misses-2
FAIL: llc misses-3
...
SUMMARY: 142 tests, 4 unexpected failures

> **
> 2. intel_cet
> gjiang@x1:~/source/kvm-unit-tests/tests> ./intel_cet
> BUILD_HEAD=73d9d850
> *skip intel_cet (test kernel not present)*
> This error looks like x86/cet.c wasn't built. Maybe do a 'make clean' and
> 'make standalone' again and watch that cet.c doesn't fail to compile.

Indeed, seems cet.c is not compiled since only cet.c exists even after run
'make clean' and 'make standalone', but tests/intel_cet is generated.

gjiang@x1:~/source/kvm-unit-tests> ls x86/cet.*
x86/cet.c

Thanks,
Guoqing

Re: kvm-unit-tests: inconsistent test result between run_tests.sh and standalone test

[Andrew Jones]

On Tue, Nov 15, 2022 at 04:53:55PM +0800, Guoqing Jiang wrote:
> Hi,
> 
> Thanks for the quick reply!
> 
> On 11/15/22 4:42 PM, Andrew Jones wrote:
> > On Tue, Nov 15, 2022 at 04:11:48PM +0800, Guoqing Jiang wrote:
> > > Hi,
> > > 
> > > I find the two test results (pmu and intel_cet) are quite different, but
> > > other
> > > test results are consistent.
> > > 
> > > gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh
> > > ...
> > > *PASS pmu (142 tests)*
> > > ...
> > > *FAIL intel_cet*
> > > ...
> > > 
> > > 1. pmu standalone test
> > > gjiang@x1:~/source/kvm-unit-tests/tests> ./pmu
> > > BUILD_HEAD=73d9d850
> > > timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot
> > > -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4
> > > -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel
> > > /tmp/tmp.Bai8UEIh2F -smp 1 -cpu max # -initrd /tmp/tmp.DFE9VFPOdp
> > > enabling apic
> > > smp: waiting for 0 APs
> > > paging enabled
> > > cr0 = 80010011
> > > cr3 = 1007000
> > > cr4 = 20
> > > PMU version:         2
> > > GP counters:         4
> > > GP counter width:    48
> > > Mask length:         7
> > > Fixed counters:      3
> > > Fixed counter width: 48
> > > PASS: core cycles-0
> > > ...
> > > FAIL: llc misses-0
> > > FAIL: llc misses-1
> > > FAIL: llc misses-2
> > > FAIL: llc misses-3
> > > ...
> > > SUMMARY: 142 tests, 4 unexpected failures
> > > *FAIL pmu (142 tests, 4 unexpected failures)
> > > 
> > > *And
> > > 
> > > gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat
> > > /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev
> > > -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio
> > > -device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat # -initrd
> > > /tmp/tmp.jiEHps3KLW
> > > enabling apic
> > > smp: waiting for 0 APs
> > > paging enabled
> > > cr0 = 80010011
> > > cr3 = 1007000
> > > cr4 = 20
> > > *SKIP: No pmu is detected!**
> > > **SUMMARY: 1 tests, 1 skipped*
> > > 
> > ./x86-run doesn't look at x86/unittests.cfg, which is where the pmu test
> > states that it needs '-cpu max'. You either need to add it yourself, e.g.
> > './x86-run ./x86/pmu.flat -cpu max' or use run_tests.sh, e.g.
> > './run_tests.sh pmu'. standalone tests get their parameters from
> > x86/unittests.cfg, which is why it's already using '-cpu max'.
> 
> Thanks for the tips. And I still see two different results, one is PASS
> while another has failures.
> 
> gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
> PASS pmu (142 tests)
> 
> gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat -cpu max
> /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev
> -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio
> -device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat -cpu max #
> -initrd /tmp/tmp.wBVHPW1XUr
> enabling apic
> smp: waiting for 0 APs
> paging enabled
> cr0 = 80010011
> cr3 = 1007000
> cr4 = 20
> PMU version:         2
> GP counters:         4
> GP counter width:    48
> Mask length:         7
> Fixed counters:      3
> Fixed counter width: 48
> ...
> FAIL: llc misses-0
> FAIL: llc misses-1
> FAIL: llc misses-2
> FAIL: llc misses-3
> ...
> SUMMARY: 142 tests, 4 unexpected failures

There shouldn't be any difference. Do the exact same failures occur every
time with standalone and never with run_tests.sh? I'll bet the failures
sometimes occur and sometimes not occur with either test invocation. In
which case, the test harness is fine, and the test cases have found
something to debug within the test and/or kvm.

> 
> > **
> > 2. intel_cet
> > gjiang@x1:~/source/kvm-unit-tests/tests> ./intel_cet
> > BUILD_HEAD=73d9d850
> > *skip intel_cet (test kernel not present)*
> > This error looks like x86/cet.c wasn't built. Maybe do a 'make clean' and
> > 'make standalone' again and watch that cet.c doesn't fail to compile.
> 
> Indeed, seems cet.c is not compiled since only cet.c exists even after run
> 'make clean' and 'make standalone', but tests/intel_cet is generated.
> 
> gjiang@x1:~/source/kvm-unit-tests> ls x86/cet.*
> x86/cet.c

Take a look at the makefile. It shows that your compiler needs to support
-fcf-protection=full.

We could consider a patch for mkstandalone like below, but I think I
prefer the way it is now, rather than silently dropping tests.

Thanks,
drew

diff --git a/scripts/mkstandalone.sh b/scripts/mkstandalone.sh
index 86c7e5498246..3d61f24d3d6e 100755
--- a/scripts/mkstandalone.sh
+++ b/scripts/mkstandalone.sh
@@ -47,9 +47,7 @@ generate_test ()
        echo "echo BUILD_HEAD=$(cat build-head)"

        if [ ! -f $kernel ]; then
-               echo 'echo "skip '"$testname"' (test kernel not present)"'
-               echo 'exit 2'
-               return
+               return 2
        fi

        echo "trap 'rm -f \$cleanup' EXIT"
@@ -89,7 +87,10 @@ function mkstandalone()

        standalone=tests/$testname

-       generate_test "$@" > $standalone
+       if ! generate_test "$@" > $standalone; then
+               rm -f $standalone
+               return
+       fi

        chmod +x $standalone
        echo Written $standalone.

Re: kvm-unit-tests: inconsistent test result between run_tests.sh and standalone test

[Guoqing Jiang]

On 11/15/22 6:29 PM, Andrew Jones wrote:
> On Tue, Nov 15, 2022 at 04:53:55PM +0800, Guoqing Jiang wrote:
>> Hi,
>>
>> Thanks for the quick reply!
>>
>> On 11/15/22 4:42 PM, Andrew Jones wrote:
>>> On Tue, Nov 15, 2022 at 04:11:48PM +0800, Guoqing Jiang wrote:
>>>> Hi,
>>>>
>>>> I find the two test results (pmu and intel_cet) are quite different, but
>>>> other
>>>> test results are consistent.
>>>>
>>>> gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh
>>>> ...
>>>> *PASS pmu (142 tests)*
>>>> ...
>>>> *FAIL intel_cet*
>>>> ...
>>>>
>>>> 1. pmu standalone test
>>>> gjiang@x1:~/source/kvm-unit-tests/tests> ./pmu
>>>> BUILD_HEAD=73d9d850
>>>> timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot
>>>> -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4
>>>> -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel
>>>> /tmp/tmp.Bai8UEIh2F -smp 1 -cpu max # -initrd /tmp/tmp.DFE9VFPOdp
>>>> enabling apic
>>>> smp: waiting for 0 APs
>>>> paging enabled
>>>> cr0 = 80010011
>>>> cr3 = 1007000
>>>> cr4 = 20
>>>> PMU version:         2
>>>> GP counters:         4
>>>> GP counter width:    48
>>>> Mask length:         7
>>>> Fixed counters:      3
>>>> Fixed counter width: 48
>>>> PASS: core cycles-0
>>>> ...
>>>> FAIL: llc misses-0
>>>> FAIL: llc misses-1
>>>> FAIL: llc misses-2
>>>> FAIL: llc misses-3
>>>> ...
>>>> SUMMARY: 142 tests, 4 unexpected failures
>>>> *FAIL pmu (142 tests, 4 unexpected failures)
>>>>
>>>> *And
>>>>
>>>> gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat
>>>> /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev
>>>> -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio
>>>> -device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat # -initrd
>>>> /tmp/tmp.jiEHps3KLW
>>>> enabling apic
>>>> smp: waiting for 0 APs
>>>> paging enabled
>>>> cr0 = 80010011
>>>> cr3 = 1007000
>>>> cr4 = 20
>>>> *SKIP: No pmu is detected!**
>>>> **SUMMARY: 1 tests, 1 skipped*
>>>>
>>> ./x86-run doesn't look at x86/unittests.cfg, which is where the pmu test
>>> states that it needs '-cpu max'. You either need to add it yourself, e.g.
>>> './x86-run ./x86/pmu.flat -cpu max' or use run_tests.sh, e.g.
>>> './run_tests.sh pmu'. standalone tests get their parameters from
>>> x86/unittests.cfg, which is why it's already using '-cpu max'.
>> Thanks for the tips. And I still see two different results, one is PASS
>> while another has failures.
>>
>> gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
>> PASS pmu (142 tests)
>>
>> gjiang@x1:~/source/kvm-unit-tests> ./x86-run ./x86/pmu.flat -cpu max
>> /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev
>> -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio
>> -device pci-testdev -machine accel=kvm -kernel ./x86/pmu.flat -cpu max #
>> -initrd /tmp/tmp.wBVHPW1XUr
>> enabling apic
>> smp: waiting for 0 APs
>> paging enabled
>> cr0 = 80010011
>> cr3 = 1007000
>> cr4 = 20
>> PMU version:         2
>> GP counters:         4
>> GP counter width:    48
>> Mask length:         7
>> Fixed counters:      3
>> Fixed counter width: 48
>> ...
>> FAIL: llc misses-0
>> FAIL: llc misses-1
>> FAIL: llc misses-2
>> FAIL: llc misses-3
>> ...
>> SUMMARY: 142 tests, 4 unexpected failures
> There shouldn't be any difference. Do the exact same failures occur every
> time with standalone and never with run_tests.sh? I'll bet the failures
> sometimes occur and sometimes not occur with either test invocation. In
> which case, the test harness is fine, and the test cases have found
> something to debug within the test and/or kvm.

The pmu standalone test always has failures though the failure numbers are
not same after every run. And './run_tests.sh pmu' which rarely reports 
failure.

gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
FAIL pmu (142 tests, 4 unexpected failures)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)
gjiang@x1:~/source/kvm-unit-tests> ./run_tests.sh pmu
PASS pmu (142 tests)

>>> **
>>> 2. intel_cet
>>> gjiang@x1:~/source/kvm-unit-tests/tests> ./intel_cet
>>> BUILD_HEAD=73d9d850
>>> *skip intel_cet (test kernel not present)*
>>> This error looks like x86/cet.c wasn't built. Maybe do a 'make clean' and
>>> 'make standalone' again and watch that cet.c doesn't fail to compile.
>> Indeed, seems cet.c is not compiled since only cet.c exists even after run
>> 'make clean' and 'make standalone', but tests/intel_cet is generated.
>>
>> gjiang@x1:~/source/kvm-unit-tests> ls x86/cet.*
>> x86/cet.c
> Take a look at the makefile. It shows that your compiler needs to support
> -fcf-protection=full.
>
> We could consider a patch for mkstandalone like below, but I think I
> prefer the way it is now, rather than silently dropping tests.

Thanks for the patch, is it possible to print more intuitive information
instead of 'test kernel not present'? I think access-reduced-maxphyaddr
is better.

gjiang@x1:~/source/kvm-unit-tests> ./tests/access-reduced-maxphyaddr
BUILD_HEAD=73d9d850
SKIP access-reduced-maxphyaddr 
(/sys/module/kvm_intel/parameters/allow_smaller_maxphyaddr not equal to Y)
> Thanks,
> drew
>
> diff --git a/scripts/mkstandalone.sh b/scripts/mkstandalone.sh
> index 86c7e5498246..3d61f24d3d6e 100755
> --- a/scripts/mkstandalone.sh
> +++ b/scripts/mkstandalone.sh
> @@ -47,9 +47,7 @@ generate_test ()
>          echo "echo BUILD_HEAD=$(cat build-head)"
>
>          if [ ! -f $kernel ]; then
> -               echo 'echo "skip '"$testname"' (test kernel not present)"'
> -               echo 'exit 2'
> -               return
> +               return 2
>          fi
>
>          echo "trap 'rm -f \$cleanup' EXIT"
> @@ -89,7 +87,10 @@ function mkstandalone()
>
>          standalone=tests/$testname
>
> -       generate_test "$@" > $standalone
> +       if ! generate_test "$@" > $standalone; then
> +               rm -f $standalone
> +               return
> +       fi
>
>          chmod +x $standalone
>          echo Written $standalone.

Thanks,
Guoqing