Re: [PATCH] Add linker_output as prefix for LTO temps (PR lto/86548).

[Martin Liška <mliska at suse dot cz>]

On 07/26/2018 01:34 PM, Richard Biener wrote:
> On Thu, Jul 26, 2018 at 12:55 PM Martin Liška <mliska@suse.cz> wrote:
>>
>> Hi.
>>
>> As requested in the PR, now we produce prefixes for temp files in LTO:
>>
>> Example:
>> $ gcc -flto main.o a.o --save-temps -o mybinary
>>
>> generates:
>> $ ls /tmp/mybinary*
>> /tmp/mybinary  /tmp/mybinary.ltrans0.o  /tmp/mybinary.ltrans0.s  /tmp/mybinary.ltrans.out
> 
> It will be /tmp/mybinary.abc421.ltrans0.o
> /tmp/mybinary.abc421.ltrans1.o, etc., correct?

Yes, --save-temps changes which file names are used. Before patch:

$ strace -f -s512 gcc -flto a.o main.o -o mybinary 2>&1 | grep execv | grep ltrans
[pid 23926] execve("/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", ["/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", "-quiet", "-dumpdir", "./", "-dumpbase", "mybinary.wpa", "-mtune=generic", "-march=x86-64", "-mtune=generic", "-march=x86-64", "-auxbase", "a", "-fno-openmp", "-fno-openacc", "-fltrans-output-list=/tmp/ccPVzNR6.ltrans.out", "-fwpa", "-fresolution=/tmp/ccuocrhY.res", "-flinker-output=exec", "@/tmp/ccHQA575"], 0x7fffffffd960 /* 105 vars */ <unfinished ...>
[pid 23928] execve("/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", ["/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", "-quiet", "-dumpdir", "./", "-dumpbase", "mybinary.ltrans0", "-mtune=generic", "-march=x86-64", "-mtune=generic", "-march=x86-64", "-auxbase-strip", "/tmp/ccPVzNR6.ltrans0.ltrans.o", "-fno-openmp", "-fno-openacc", "-fltrans", "@/tmp/ccssDdS8", "-o", "/tmp/cclsKY4G.s"], 0x7fffffffd960 /* 105 vars */ <unfinished ...>
[pid 23929] execve("/home/marxin/bin/gcc/bin//as", ["as", "--64", "-o", "/tmp/ccPVzNR6.ltrans0.ltrans.o", "/tmp/cclsKY4G.s"], 0x7fffffffd960 /* 105 vars */) = -1 ENOENT (No such file or directory)
[pid 23929] execve("/home/marxin/bin/as", ["as", "--64", "-o", "/tmp/ccPVzNR6.ltrans0.ltrans.o", "/tmp/cclsKY4G.s"], 0x7fffffffd960 /* 105 vars */) = -1 ENOENT (No such file or directory)
[pid 23929] execve("/usr/local/bin/as", ["as", "--64", "-o", "/tmp/ccPVzNR6.ltrans0.ltrans.o", "/tmp/cclsKY4G.s"], 0x7fffffffd960 /* 105 vars */) = -1 ENOENT (No such file or directory)
[pid 23929] execve("/usr/bin/as", ["as", "--64", "-o", "/tmp/ccPVzNR6.ltrans0.ltrans.o", "/tmp/cclsKY4G.s"], 0x7fffffffd960 /* 105 vars */ <unfinished ...>

after:

$ strace -f -s512 gcc -flto a.o main.o -o mybinary 2>&1 | grep execv | grep ltrans
[pid 16379] execve("/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", ["/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", "-quiet", "-dumpdir", "./", "-dumpbase", "mybinary.wpa", "-mtune=generic", "-march=x86-64", "-mtune=generic", "-march=x86-64", "-auxbase", "a", "-fno-openmp", "-fno-openacc", "-fltrans-output-list=/tmp/mybinary.VkVmXd.ltrans.out", "-fwpa", "-fresolution=/tmp/ccnQ6e55.res", "-flinker-output=exec", "@/tmp/cc0Sv5Fe"], 0x7fffffffd960 /* 105 vars */ <unfinished ...>
[pid 16381] execve("/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", ["/home/marxin/bin/gcc/lib/gcc/x86_64-pc-linux-gnu/9.0.0/lto1", "-quiet", "-dumpdir", "./", "-dumpbase", "mybinary.ltrans0", "-mtune=generic", "-march=x86-64", "-mtune=generic", "-march=x86-64", "-auxbase-strip", "/tmp/mybinary.VkVmXd.ltrans0.ltrans.o", "-fno-openmp", "-fno-openacc", "-fltrans", "@/tmp/ccDY6Ojf", "-o", "/tmp/ccrmLPAG.s"], 0x7fffffffd960 /* 105 vars */ <unfinished ...>
[pid 16382] execve("/home/marxin/bin/gcc/bin//as", ["as", "--64", "-o", "/tmp/mybinary.VkVmXd.ltrans0.ltrans.o", "/tmp/ccrmLPAG.s"], 0x7fffffffd960 /* 105 vars */) = -1 ENOENT (No such file or directory)
[pid 16382] execve("/home/marxin/bin/as", ["as", "--64", "-o", "/tmp/mybinary.VkVmXd.ltrans0.ltrans.o", "/tmp/ccrmLPAG.s"], 0x7fffffffd960 /* 105 vars */) = -1 ENOENT (No such file or directory)
[pid 16382] execve("/usr/local/bin/as", ["as", "--64", "-o", "/tmp/mybinary.VkVmXd.ltrans0.ltrans.o", "/tmp/ccrmLPAG.s"], 0x7fffffffd960 /* 105 vars */) = -1 ENOENT (No such file or directory)
[pid 16382] execve("/usr/bin/as", ["as", "--64", "-o", "/tmp/mybinary.VkVmXd.ltrans0.ltrans.o", "/tmp/ccrmLPAG.s"], 0x7fffffffd960 /* 105 vars */ <unfinished ...>


> 
> Otherwise there's the chance to trash user files which isn't good.

Sure, the patch behaves fine. I'll install it.

Martin

> 
>> Patch can bootstrap on ppc64le-redhat-linux and survives regression tests.
>>
>> Ready to be installed?
> 
> OK if the above is correct.
> 
> Thanks,
> Richard.
> 
>> Martin
>>
>> gcc/ChangeLog:
>>
>> 2018-07-26  Martin Liska  <mliska@suse.cz>
>>
>>         PR lto/86548
>>         * lto-wrapper.c: Add linker_output as prefix
>>         for ltrans_output_file.
>>
>> include/ChangeLog:
>>
>> 2018-07-26  Martin Liska  <mliska@suse.cz>
>>
>>         PR lto/86548
>>         * libiberty.h (make_temp_file_with_prefix): New function.
>>
>> libiberty/ChangeLog:
>>
>> 2018-07-26  Martin Liska  <mliska@suse.cz>
>>
>>         PR lto/86548
>>         * make-temp-file.c (TEMP_FILE): Remove leading 'cc'.
>>         (make_temp_file): Call make_temp_file_with_prefix with
>>         first argument set to NULL.
>>         (make_temp_file_with_prefix): Support also prefix.
>> ---
>>  gcc/lto-wrapper.c          | 14 +++++++++++++-
>>  include/libiberty.h        |  5 +++++
>>  libiberty/make-temp-file.c | 24 ++++++++++++++++++------
>>  3 files changed, 36 insertions(+), 7 deletions(-)
>>
>>