Richard Guenther - Re: [fortran] Disable use of -malign-double (original) (raw)

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• From: "Richard Guenther"
• To: "Jerry DeLisle"
• Cc: "Andrew Pinski" , "Steve Kargl" , fortran at gcc dot gnu dot org, gcc-patches at gcc dot gnu dot org
• Date: Thu, 1 Feb 2007 10:48:17 +0100
• Subject: Re: [fortran] Disable use of -malign-double
• References: 200701311824.l0VIORT3025323@localhost.localdomain <45C1515A.1070304@verizon.net>

On 2/1/07, Jerry DeLisle jvdelisle@verizon.net wrote:

(Note I agree with Andrew that no special action should be required, the documentation is quite clear)

I think we should have a test at compile time to determine if the libraries have been aligned and if not issue an error if -malign-double is used. I am not sure exactly how we would do this, but maybe add a simple structure and test function in the library that is called at compile time to answer the question.

A compile time test will not work (think of shared libraries and moving a binary).

We could make this function callable as part of initialization of main or in start_library to issue a runtime error or warning as well.

What you can do is at runtime program initialization time do a check if the program and libgfortran have been compiled with a compatible ABI, but of course this doesn't cover other libraries such as blas or glibc.

The only sane way to do it is marking your objects in a way that the linker and dynamic loader can reject incompatible versions.

(Note I agree with Andrew that no special action should be required, the documentation is quite clear)

Richard.

• Follow-Ups:
  • Re: [fortran] Disable use of -malign-double
    * From: François-Xavier Coudert
  • Re: [fortran] Disable use of -malign-double
    * From: Erik Schnetter
• References:
  • Re: [fortran] Disable use of -malign-double
    * From: Jerry DeLisle