Re: Ping: [PATCH] testsuite/C++: suppress filename canonicalization in module tests

[Nathan Sidwell <nathan@acm.org>]

On 4/25/23 11:04, Jan Beulich wrote:
> On 28.06.2022 16:06, Jan Beulich wrote:
>> The pathname underneath gcm.cache/ is determined from the effective name
>> used for the main input file of a particular module. When modules are
>> built, no canonicalization occurs for the main input file. Hence the
>> module file wouldn't be found if a different (the canonicalized) file
>> name was used when importing that same module. (This is an effect of
>> importing happening in the preprocessor, just like #include handling.)
>>
>> Since it doesn't look easy to make module generation use libcpp's
>> maybe_shorter_path() (in fact I'd consider this a layering violation,
>> while cloning the logic would - at least in principle - be prone to both
>> going out of sync), simply suppress system header path canonicalization
>> for the respective tests.
> 
> Ping: This still looks to apply as is.

ok -- I was unaware of this.  might be sensible to file a defect about this?

> 
> Thanks, Jan
> 
>> ---
>> Strictly speaking it could be necessary to also suppress
>> canonicalization when generating the modules, but for now they're self-
>> contained, i.e. don't include any "real" system headers. IOW at the
>> moment the tests aren't susceptible to the issue at generation time.
>>
>> --- a/gcc/testsuite/g++.dg/modules/alias-1_b.C
>> +++ b/gcc/testsuite/g++.dg/modules/alias-1_b.C
>> @@ -1,4 +1,4 @@
>> -// { dg-additional-options "-fmodules-ts -fdump-lang-module -isystem [srcdir]" }
>> +// { dg-additional-options "-fmodules-ts -fdump-lang-module -isystem [srcdir] -fno-canonical-system-headers" }
>>   
>>   // Alias at the header file.  We have one CMI file
>>   import "alias-1_a.H";
>> --- a/gcc/testsuite/g++.dg/modules/alias-1_d.C
>> +++ b/gcc/testsuite/g++.dg/modules/alias-1_d.C
>> @@ -1,4 +1,4 @@
>> -// { dg-additional-options "-fmodules-ts -isystem [srcdir]" }
>> +// { dg-additional-options "-fmodules-ts -isystem [srcdir] -fno-canonical-system-headers" }
>>   // { dg-module-cmi kevin }
>>   
>>   export module kevin;
>> --- a/gcc/testsuite/g++.dg/modules/alias-1_e.C
>> +++ b/gcc/testsuite/g++.dg/modules/alias-1_e.C
>> @@ -1,4 +1,4 @@
>> -// { dg-additional-options "-fmodules-ts -isystem [srcdir]" }
>> +// { dg-additional-options "-fmodules-ts -isystem [srcdir] -fno-canonical-system-headers" }
>>   
>>   import bob;
>>   import kevin;
>> --- a/gcc/testsuite/g++.dg/modules/alias-1_f.C
>> +++ b/gcc/testsuite/g++.dg/modules/alias-1_f.C
>> @@ -1,4 +1,4 @@
>> -// { dg-additional-options "-fmodules-ts -fdump-lang-module -isystem [srcdir]" }
>> +// { dg-additional-options "-fmodules-ts -fdump-lang-module -isystem [srcdir] -fno-canonical-system-headers" }
>>   
>>   import kevin;
>>   import bob;
>> --- a/gcc/testsuite/g++.dg/modules/cpp-6_c.C
>> +++ b/gcc/testsuite/g++.dg/modules/cpp-6_c.C
>> @@ -1,5 +1,5 @@
>>   // { dg-do preprocess }
>> -// { dg-additional-options "-fmodules-ts -isystem [srcdir]" }
>> +// { dg-additional-options "-fmodules-ts -isystem [srcdir] -fno-canonical-system-headers" }
>>   
>>   #define empty
>>   #define nop(X) X
>> --- a/gcc/testsuite/g++.dg/modules/dir-only-2_b.C
>> +++ b/gcc/testsuite/g++.dg/modules/dir-only-2_b.C
>> @@ -1,5 +1,5 @@
>>   // { dg-do preprocess }
>> -// { dg-additional-options "-fmodules-ts -fdirectives-only -isystem [srcdir]" }
>> +// { dg-additional-options "-fmodules-ts -fdirectives-only -isystem [srcdir] -fno-canonical-system-headers" }
>>   // a comment
>>   module; // line
>>   frob
> 

-- 
Nathan Sidwell