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From: "Raut, S Biplab" <Biplab.Raut@amd.com>
To: "gcc-help@gcc.gnu.org" <gcc-help@gcc.gnu.org>
Subject: Compile time errors on using target attribute for Function Multi Versioning
Date: Fri, 22 Apr 2022 07:09:18 +0000	[thread overview]
Message-ID: <DM4PR12MB5166A2758E1C4963C09422D6F5F79@DM4PR12MB5166.namprd12.prod.outlook.com> (raw)

Hi All,
          I want to support Function Multi Versioning (FMV) in my code by using GCC's "target" attribute.
Few functions in my program are hand-written intrinsic codes, so I would prefer to use "target" over "target_clones" attribute.
But, I am getting function redefinition errors for the multiple versions of the function when I try to compile the test program.

Please find the details below:
Source code is based on:- https://gcc.gnu.org/wiki/FunctionMultiVersioning#:~:text=1%20__attribute__%20((target,return%200%3B%0A%20%2033%20%7D
GCC version used:- 11.2.0
OS used:- Ubuntu 21.10
Errors encountered:- (test_target.c is the name of source file containing the FMV example code)
$ gcc test_target.c
test_target.c:12:5: error: redefinition of 'foo'
   12 | int foo ()
      |     ^~~
test_target.c:5:5: note: previous definition of 'foo' with type 'int()'
    5 | int foo ()
      |     ^~~
test_target.c:19:5: error: redefinition of 'foo'
   19 | int foo ()
      |     ^~~
test_target.c:5:5: note: previous definition of 'foo' with type 'int()'
    5 | int foo ()
      |     ^~~
test_target.c:26:5: error: redefinition of 'foo'
   26 | int foo ()
      |     ^~~
test_target.c:5:5: note: previous definition of 'foo' with type 'int()'
    5 | int foo ()
      |     ^~~

Am I missing something here in terms of compilation flags or otherwise.
Can you please help me to get this example working. Based on this example, I will need to change my actual program.

If this group is not meant for such questions/help, please guide me to the right mailing group.

With Regards,
S. Biplab Raut

             reply	other threads:[~2022-04-22  7:09 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-22  7:09 Raut, S Biplab [this message]
2022-04-22  7:36 ` Xi Ruoyao
2022-04-22  8:17   ` Raut, S Biplab
2022-04-22  9:27     ` Xi Ruoyao

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