[PATCH 1/2] stdio-common: run AWK in the C locale in the printf format tests
Adhemerval Zanella Netto
adhemerval.zanella@linaro.org
Tue Aug 4 13:37:28 GMT 2026
On 04/08/26 10:18, Adhemerval Zanella Netto wrote:
>
>
> On 03/08/26 22:59, Matt Turner wrote:
>> The program under test runs in the C locale, through the test program
>> prefix, but AWK inherits whatever locale the build was started in. They
>> agree today only because the locale in use shares its decimal point with
>> the C locale.
>>
>> It is also faster. gawk takes a single byte path in its regular
>> expression engine when MB_CUR_MAX is 1, and the script matches several
>> expressions against every line. For the %f conversion for double, the
>> largest of these tests, as the median of five runs:
>>
>> x86_64, gawk 5.4.1 1.482s -> 1.248s
>> x86_64, gawk 5.3.2 0.911s -> 0.703s
>> alpha, gawk 5.4.60 30.9s -> 26.6s
>>
>> Worth noting that gawk 5.4 is a good deal slower here than 5.3 was, at
>> 1.248s against 0.703s for the same input in the C locale, so these tests
>> have become more expensive than they used to be.
>
> LGTM, thanks.
>
> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Scratch that, testing shows that LC_ALL=C expansion is not working correctly:
$ cat stdio-common/tst-printf-format-as-c.out
Verifying c
Conversion c output error, first line:
tst-printf-format-c.sh: line 32: LC_ALL=C: command not found
The scripts invoke '$AWK -f tst-printf-format.awk', shell recognizes VAR=value
assignment prefixes at parse time, before variable expansion. You need to use
'env' here:
AWK="env LC_ALL=C ${AWK:-awk}"
>
>> ---
>> stdio-common/tst-printf-format-c.sh | 2 +-
>> stdio-common/tst-printf-format-char.sh | 2 +-
>> stdio-common/tst-printf-format-double.sh | 2 +-
>> stdio-common/tst-printf-format-int.sh | 2 +-
>> stdio-common/tst-printf-format-ldouble.sh | 2 +-
>> stdio-common/tst-printf-format-llong.sh | 2 +-
>> stdio-common/tst-printf-format-long.sh | 2 +-
>> stdio-common/tst-printf-format-s.sh | 2 +-
>> stdio-common/tst-printf-format-short.sh | 2 +-
>> stdio-common/tst-printf-format-uchar.sh | 2 +-
>> stdio-common/tst-printf-format-uint.sh | 2 +-
>> stdio-common/tst-printf-format-ullong.sh | 2 +-
>> stdio-common/tst-printf-format-ulong.sh | 2 +-
>> stdio-common/tst-printf-format-ushort.sh | 2 +-
>> 14 files changed, 14 insertions(+), 14 deletions(-)
>>
>> diff --git ./stdio-common/tst-printf-format-c.sh ./stdio-common/tst-printf-format-c.sh
>> index 825c50ec42..636884d3a7 100644
>> --- ./stdio-common/tst-printf-format-c.sh
>> +++ ./stdio-common/tst-printf-format-c.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> echo Verifying c
>> (set -o pipefail
>> diff --git ./stdio-common/tst-printf-format-char.sh ./stdio-common/tst-printf-format-char.sh
>> index 7867bdd62f..a3eb0665f2 100644
>> --- ./stdio-common/tst-printf-format-char.sh
>> +++ ./stdio-common/tst-printf-format-char.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=0
>>
>> diff --git ./stdio-common/tst-printf-format-double.sh ./stdio-common/tst-printf-format-double.sh
>> index 8157092dc4..ddbffd19aa 100644
>> --- ./stdio-common/tst-printf-format-double.sh
>> +++ ./stdio-common/tst-printf-format-double.sh
>> @@ -29,7 +29,7 @@ test_program_prefix=$1; shift
>> # internally to process the conversion requested, so any bug in our code
>> # would then be verified against itself, defeating the objective of doing
>> # the verification against an independent implementation.
>> -AWK="${AWK:-awk} -M"
>> +AWK="LC_ALL=C ${AWK:-awk} -M"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-int.sh ./stdio-common/tst-printf-format-int.sh
>> index 8542ff4150..2cca1dc884 100644
>> --- ./stdio-common/tst-printf-format-int.sh
>> +++ ./stdio-common/tst-printf-format-int.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-ldouble.sh ./stdio-common/tst-printf-format-ldouble.sh
>> index dbf78a98c6..9acb1237de 100644
>> --- ./stdio-common/tst-printf-format-ldouble.sh
>> +++ ./stdio-common/tst-printf-format-ldouble.sh
>> @@ -29,7 +29,7 @@ test_program_prefix=$1; shift
>> # internally to process the conversion requested, so any bug in our code
>> # would then be verified against itself, defeating the objective of doing
>> # the verification against an independent implementation.
>> -AWK="${AWK:-awk} -M"
>> +AWK="LC_ALL=C ${AWK:-awk} -M"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-llong.sh ./stdio-common/tst-printf-format-llong.sh
>> index e1f5252c9a..5e10e87fa6 100644
>> --- ./stdio-common/tst-printf-format-llong.sh
>> +++ ./stdio-common/tst-printf-format-llong.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-long.sh ./stdio-common/tst-printf-format-long.sh
>> index 4b68ab1e04..0e17fcd596 100644
>> --- ./stdio-common/tst-printf-format-long.sh
>> +++ ./stdio-common/tst-printf-format-long.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-s.sh ./stdio-common/tst-printf-format-s.sh
>> index 65aa0cb675..d0a2ffd166 100644
>> --- ./stdio-common/tst-printf-format-s.sh
>> +++ ./stdio-common/tst-printf-format-s.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> echo Verifying s
>> (set -o pipefail
>> diff --git ./stdio-common/tst-printf-format-short.sh ./stdio-common/tst-printf-format-short.sh
>> index 30357baa02..bd759b5bb7 100644
>> --- ./stdio-common/tst-printf-format-short.sh
>> +++ ./stdio-common/tst-printf-format-short.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=0
>>
>> diff --git ./stdio-common/tst-printf-format-uchar.sh ./stdio-common/tst-printf-format-uchar.sh
>> index 08a6914b88..6f41009ad3 100644
>> --- ./stdio-common/tst-printf-format-uchar.sh
>> +++ ./stdio-common/tst-printf-format-uchar.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=0
>>
>> diff --git ./stdio-common/tst-printf-format-uint.sh ./stdio-common/tst-printf-format-uint.sh
>> index 0ba203ccda..be2da0064b 100644
>> --- ./stdio-common/tst-printf-format-uint.sh
>> +++ ./stdio-common/tst-printf-format-uint.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-ullong.sh ./stdio-common/tst-printf-format-ullong.sh
>> index 5b881ab924..45dfafb682 100644
>> --- ./stdio-common/tst-printf-format-ullong.sh
>> +++ ./stdio-common/tst-printf-format-ullong.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-ulong.sh ./stdio-common/tst-printf-format-ulong.sh
>> index f6aeb8e3c0..24e36cbccf 100644
>> --- ./stdio-common/tst-printf-format-ulong.sh
>> +++ ./stdio-common/tst-printf-format-ulong.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=77
>>
>> diff --git ./stdio-common/tst-printf-format-ushort.sh ./stdio-common/tst-printf-format-ushort.sh
>> index 07609128ab..0e1008c75e 100644
>> --- ./stdio-common/tst-printf-format-ushort.sh
>> +++ ./stdio-common/tst-printf-format-ushort.sh
>> @@ -23,7 +23,7 @@ xprintf=$1; shift
>> common_objpfx=$1; shift
>> test_program_prefix=$1; shift
>>
>> -AWK=${AWK:-awk}
>> +AWK="LC_ALL=C ${AWK:-awk}"
>>
>> status=0
>>
>
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