Compiling with ifx (compile option: /od) outputs a large .obj (compared to ifort)

[hmatsuo]

Without optimization, I would like to know if there is a way to make a small size .obj.
        If I optimize it, it will be difficult to debug.
        Without optimization, I want to make a small size .obj.
    Platform : Windows x64

The results of the survey are as follows.

- I was able to make a small size .obj by the following method.
        Do not specify /Od

        The number of bytes of .obj created by compiling a source.
        Compilation Option and .obj-size(bytes)
               /Od              Yes                  No
              -----------------------------------------
              ifort 19        19,989 *a          8,697
              ifort 2021   19,943               8,792
              ifx 2024    271,474 *b       10,996 *c

- Considering changing iFort to ifx.
        Until now, it was *a.
        In ifx, if /OD is specified, *b is obtained
        In ifx, if /OD is not specified, *c is obtained

- I compiled with /Od and /nodebug, but the size of .obj was the same as when /Od was specified.

- Size of .exe linked with other .obj and .lib.
        *a       86,597Kbytes
        *b    184,088Kbytes (huge)
        *c       81,290Kbytes

- If /Od is not specified, The size of the obj will be smaller.
  I'm guessing that the optimization default, /O2, will be specified.

[andrew_4619]

" I would like to know if there is a way to make a small size .obj"

Why? Does it matter? 

[hmatsuo]

Even if it's 64-bit, Less memory means faster response times.
Since the data to be handled is large, we want to make the program as small as possible.
I think it's an important issue.

[jimdempseyatthecove]

If (when) "size matters", compile the fully debugged sections of code with optimizations enabled, and compile the necessary source files with no optimizations and debugging enabled.

In MS VS Solution Explorer, right-click on a source file, then set the specific compiler optimizations for that file.

Not, it is often beneficial to add a configuration

Debug - Full debug

Release - Full Release

ReleaseDebug - mostly Release, some Debug

...

Jim Dempsey

[hmatsuo]

I understand what is being said.

I'm experiencing a bug in the optimization with another compiler that isn't an Intel compiler.
Because of that, I want to use it without optimizing it.

I understand that ifort and ifx have different compilers, so the object files are different.
However, since the ifx object is more than 10 times larger than the ifort,
I would like to know if there is a way to make a small size .obj of ifx.

[jimdempseyatthecove]

Does the ifx debug build have array bounds checking enabled and ifort not?

To a lesser extent does the ifx debug build have uninitialized variable checking enabled and ifort not?

Jim Dempsey

[hmatsuo]

The options specified for ifort and ifx are the same.
   /fpp /c /Od /D_WIN64 /Qm64 /warn:declarations /warn /Qsave /GS /nogen-interfaces

I checked the options in /help, but I couldn't find any description that the default had changed.
I'd like to know which option you are talking about.

[Steve_Lionel]

It would be very useful if you could attach a small source file that demonstrates the problem. By any chance does this source declare large arrays with initialization?

[hmatsuo]

Attach the source files next week.
(I'm going out on a business trip from now on.)

The source in question does not declare large arrays.
The largest one is INTEGER*8 ARRAY(16).

[hmatsuo]

I'm very, very sorry for the delay.

From the original object tendencies, I created a simple source.
    ODSIZE_00.f
    ODSZIE_01.f
    OD_ALIAS.h

    The differences between ODSIZE_00.f and ODSIZE_01.f are as follows:
        ODSIZE_00.f(6): C#include "OD_ALIAS.h"
        ODSIZE_01.f(6): #include "OD_ALIAS.h"
    In OD_ALIAS.h, "!DIR$ ALIAS" is described in 100 lines.
    However, these 100 are symbol names that are not referenced in the source file.

The compile options were specified as follows:
    /fpp /c /Od /I. /D_WIN64 /Qm64 /warn:declarations /warn /Qsave /GS /nogen-interfaces
    (Windows x64)

The file size of the created .obj is as follows:
                        ODSIZE_00.f     ODSZIE_01.f
    ifort 2021   1,324 bytes      1,324 bytes
    ifx 2024      1,590 bytes      5,023 bytes

When I check the .obj with dumpbin, "RAW DATA #5" is replaced by "!DIR$ALIAS".

Information about the system I'm developing.
    - The system is created in Fortran and C.
    - A single source file allows for 32-bit and 64-bit compilation.
    - "!DIR$ ALIAS" is used to replace the symbol name.
    - More than 6,000 "!DIR$ ALIAS" are registered in the include files used by all sources.
        Therefore, in some source files, "!DIR$ ALIAS" is also described as unreferenced.

If I don't specify the compile option "/Od" (i.e. "/O2"), then The file size of .obj is as follows:
                        ODSIZE_00.f   ODSZIE_01.f
    ifort 2021 1,132 bytes     1,132 bytes
    ifx 2024    1,409 bytes     1,409 bytes

I'm wondering if the unused information for "DIR$ALIAS" is left if I specify "/Od".