PING Re: [patch] PR debug/46102 Disable -feliminate-dwarf2-dups when reading a PCH

[Aldy Hernandez]

On 02/19/2015 10:41 AM, Jakub Jelinek wrote:
> On Thu, Feb 19, 2015 at 10:33:20AM -0800, Aldy Hernandez wrote:
>> Well, any PCH file we generate will have some sort of early DIE in it (at
>> the very least the compilation unit DIE) and we will read these in at PCH
>> read-in time, obliterating whatever was already there.  But most
>> importantly, with the attached patch we will not use these
>> DW_TAG_GNU_[BE]INCL* DIEs, since the reader will avoid reading the pch file.
>> So, I don't think erroring out at output time is necessary.
>>
>> How does this look?
>
> Looks reasonable to me, but I'd prefer to defer this to Jason as debug
> maintainer.
>
>> commit d90a408ad21aa0868cc13de24ea38e210ef78a68
>> Author: Aldy Hernandez <aldyh@redhat.com>
>> Date:   Thu Feb 19 07:35:59 2015 -0800
>>
>>      	PR debug/46102
>>      	* c-pch.c (c_common_valid_pch): Mark PCH file with
>>      	-feliminate-dwarf2-dups as invalid.
>>
>> diff --git a/gcc/c-family/c-pch.c b/gcc/c-family/c-pch.c
>> index 0ede92a..55163c9 100644
>> --- a/gcc/c-family/c-pch.c
>> +++ b/gcc/c-family/c-pch.c
>> @@ -224,6 +224,19 @@ c_common_valid_pch (cpp_reader *pfile, const char *name, int fd)
>>     const char *pch_ident;
>>     struct c_pch_validity v;
>>
>> +  /* We may have outputted a few DIEs corresponding to
>> +     DW_TAG_GNU_[BE]INCL.  Reading the compiler state later will read
>> +     in these DIEs, and obliterate any DW_TAG_GNU_[BE]INCL the reader
>> +     may have generated itself.  Do not read the PCH if this may
>> +     happen.  */
>> +  if (flag_eliminate_dwarf2_dups)
>> +    {
>> +      if (cpp_get_options (pfile)->warn_invalid_pch)
>> +	cpp_error (pfile, CPP_DL_WARNING,
>> +		   "%s: cannot be used with -feliminate-dwarf2-dups", name);
>> +      return 2;
>> +    }
>> +
>>     /* Perform a quick test of whether this is a valid
>>        precompiled header for the current language.  */
>>
>
>
> 	Jakub
>