AIX binaries - size & symbols - unix

There are a few differences noticed in symbols between two binaries built using same sources on two AIX systems. One example for 'main':
xxxx1: .main T 4294975624
xxxx2: .main T 4294969472 516
xxxx2: main:F-1 - 0
Why the difference in sizes?
'T' is Global text symbol as per man page. What is 'F'?
Also, the sizes of two binaries vary significantly: 3924048 vs. 17701460. Why?
AIX versions, compiler versions, makefiles (same CFLAGS) are identical.

I'm fairly sure the F-1 is a function returning int. It is a "stab" string which is output when the compiler given the -g option. That would also be the reason for the size differences.
Can you try doing "size " and "size ". size also has an option to make it more verbose. You can also do "file " etc and it will tell you if it is stripped or not.
Between the -g and the strip flag at link time, I think that will account for the differences you are seeing.
HTH

Related

clearmake doesn't like my MAKEFLAGS=j12 values

I use both GNU Make and - woe is me - ClearCase' clearmake.
Now, GNU make respect a flag named MAKEFLAGS, which for me is set to j20 on this multi-core machine I'm on. Unfortunately, clearmake also recognizes this option, yet doesn't except this value. It tells me:
clearmake: Error: Bad option (j)
clearmake: Error: Bad option (2)
clearmake: Error: Bad option (0)
Questions:
Why is this happening? Should ClearMake accommodate GNU Make's usage?
How can I get around it, other then turning the flag off an on repeatedly?
It's been 15 years or so since I used clearmake, but assuming it doesn't support the GNU make-specific GNUMAKEFLAGS variable you can use:
export GNUMAKEFLAGS=-j20
and leave MAKEFLAGS unset.
The "BUILDING SOFTWARE WITH CLEARCASE" clearly states in its T"unsupported Gnu make features" that this option is indeed not supported.
–j [JOBS]
--jobs=[JOBS]
Maybe a clearmake -C -J can help (for testing): there should then be no limit to the number of parallel builds.
Are you calling GNU make from a clearmake build script? Or are you trying to create a single makefile that will support both build tools? I think the GNUMAKEFLAGS EV is safer for GNU make specific values. I would also use
CCASE_MAKEFLAGS for any makeflags that are specific to clearmake.
CCASE_CONC to set the concurrency value. While clearmake no longer passes the -J in MAKEFLAGS, it used to, and if you're using an older clearmake (somewhere in the 7's as I recall), you could upset "child" GNU make sessions since they like -J about as much as clearmake likes -j.
Finally, check the env_ccase man page for the behavior mentioned in CCASE_MAKEFLAGS_V6_OBSOLETE. If you pass MAKEFLAGS explicitly in the build script like
$(MAKE) $(MAKEFLAGS) TARGET=x
And had started clearmake like this:
clearmake -C gnu TARGET=Y
You'll actually get both TARGET macro definitions in the command line. Setting the mentioned EV (at all) avoids the "pass defined macros in MAKEFLAGS" behavior. The switch exists because some people have makefiles that DEPEND on this behavior, while others have ones BROKEN BY this behavior...
Assuming for the sake of argument that your company has a support agreement with either IBM or HCL, this is a good time to use your support channels to bring up clearmake concerns.

GNAT Metric and RTL files

For running GNAT metric (for Windows, GPL 2017 or CE 2018) I'd like to include the RTL sources as well. There is a "-a" switch but it seems to be ineffective. When I'm forcing visibility of RTL sources, only ada.ads and system.ads are processed. Guessing it is a "crunched name" issue (RTL file names forced to 8 character names) I've tried other tricks without success.
My question is: is there a way to get the RTL source metrics (of the source files actually used) with GNAT Metric?
I'm using the command
gnatmetric -a -xs -nt -j0 -Pmyproj.gpr -U somemain.adb
TIA
In the meantime I've found a workaround by using the gnathtml.pl script.
I've customized the script a bit by removing the H1 headers.
The result is a few hundreds of HTML files with the sources of units actually used: the script does find all dependencies, recursively, through the .ali files - including the RTL.
Then I group the HTML files together, convert them back to text files, pass them through Adalog's Normalize tool for removing comments and empty lines, count lines with the wc command, and the job is done.

Intel icc compiler -O flags and -qopt-report

I am working on a HPC at the moment, and I have a question regarding the icc compiler.
What I want to do is to have a peek at what is going on when I change the optimisation levels through [O0..O3]. The data I want, regarding vectorization and whether code was folded inline etc., seems to be in the report generated by the -qopt-report flag.
I decided to use the greatest level of verbosity for the report which is
-qopt-report5 (I think this is the correct way to use it)
however, when reducing the O-level, the report gets progressively smaller until becoming empty when using the -O0 flag:
icc -O0 -qopt-report5 -c test1.c
I'll keep looking, but if anyone notices me being brain dead, I'd appreciate a pointer to the use of these flags together!
Thanks in advance for any hints.
Cheers,
MArk.
-qopt-report5 is always disabled when you use -O0.
This is "by definition", because opt-report == "optimization report" and O0 == "no optimization", so there is nothing to report about.
Auto-vectorization is generally speaking enabled starting from O2 optimizaiton level, so if you want to explore vectorization aspects, then you need to use at least "-O2 -opt-report5" combination or "higher".
If you want to correlate performance "peaks" and "optimization report", consider using Intel "Vectorization Advisor" (read more here, download from this location for now: https://software.intel.com/en-us/advisor_getting_started_intro )

Using the diff command

So I am trying to compare a binary file I make when I compile with gcc to an sample executable that is provided. So I used the command diff and went like this
diff asgn2 sample-asgn2
Binary files asgn2 and sample-asgn2 differ
Is there any way to see how they differ? Instead of it just displaying that differ.
Do a hex dump of the two binaries using hexdump. Then you can compare the hex dump using your favorite diffing tool, like kdiff3, tkdiff, xxdiff, etc.
Why don't you try Vbindiff? It probably does what you want:
Visual Binary Diff (VBinDiff) displays files in hexadecimal and ASCII (or EBCDIC). It can also display two files at once, and highlight the differences between them. Unlike diff, it works well with large files (up to 4 GB).
Where to get Vbindiff depends on which operating system you are using. If Ubuntu or another Debian derivative, apt-get install vbindiff.
I'm using Linux,in my case,I need a -q option to just show what you got.
diff -q file1 file2
without -q option it will show which line is differ and display that line.
you may check with man diff to see the right option to use in your UNIX.
vbindiff only do byte-to-byte comparison. If there is just one byte addition/deletion, it will mark all subsequent bytes changed...
Another approach is to transform the binary files in text files so they can be compared with the text diff algorithm.
colorbindiff.pl is a simple and open-source perl script which uses this method and show a colored side-by-side comparison, like in a text diff. It highlights byte changes/additions/deletions. It's available on GitHub.

console print w/o scrolling

I see console apps print colors and seen apps such as ffmpeg print text over itself instead of a new line. How do I print over an existing line? I want to display fps in my console app either at the very top or very bottom and have regular printfs go there and scroll normally.
I need this for windows, but this is meant to be cross platform, so I will eventually have a linux and mac implementation.
There is two simple possibilities which work on linux as well as windows, but only for one line:
printf("\b"); will return for one character, so you might count how many character you want to backspace and fire this in a loop, or you know that you only write n numbers and do it likeprintf("\b\b\b\b\b\b\b\b\b\b");
printf("text to be overwritten by next printf\r"); this will return the cursor to the beginning of the line, so any next printf will overwrite it. Make sure to write a string of same length or longer so you overwrite it entirely.
If you want to rewrite several lines, there is nothing so portable as ncurses, there is libs for it on practically every operating system, and you don't have to take care of the ANSI-differences.
edit: added link to ncurses wikipedia page, gives great overview and introduction, as well as link list and maybe a translation to your preferred language
Check out ncurses. It has bindings for most scripting languages.
You can use '\r' instead of '\n'.
The ASCII character number 8 (A.K.A. Ctrl-H, BS or Backspace) lets you back up one character. ASCII Character number 13 (A.K.A Ctrl-M, CR or Carriage Return) returns the cursor at the beggining of the line.
If you are working in C try putchar(8); and putchar(13);
The magic of the colors, cursor locating and bliking and so on are inside ANSI escape codes. Any text console capable of handling ANSI codes can use them just printing them out to console (i.e. by means of echo in a bash script or printf() function in C).
Unix terminals support ANSI escape sequences and Windows world used to support them back in old MS-DOS days, but the multibyte console support put an end to this. There is more information here. However there are other ways out of just ANSI sequences printing available on Windows. Moreover if you have Cygwin installed on your Windows maching ANSI codes work just as great as on any Unix terminal.
Many people mention Ncurses library that is the de-facto standard for any gui-like text based applications. What this library does is to hide all the terminal differences (Windows/Unix flavours) to represent the same information as identical as possible across all the platforms, though from my own experience I tell you this is not always true (i.e. typical text window frames change because the especial chars are not available under all character encodings). The counterpart of using ncurses is that it is a complete API and it is much harder to start out with it than simply writing out some ANSI escape sequences for simple things such as change the font color, cleaning screen or moving back the cursor to a random position.
For the sake of completeness I paste an example of use of ANSI sequence under Linux that changes the prompt to blue and shows the date:
PS1="\[\033[34m\][\$(date +%H%M)][\u#\h:\w]$ "
You can use Ncurses -
ncurses package is a subroutine library for terminal-independent screen-painting and input-event handling which presents a high level screen model to the programmer, hiding differences between terminal types and doing automatic optimization of output to change one screenfull of text into another
Depending on the platform which you are developing on there's probably a more powerful API which you could use, rather than old ASCII control codes.
e.g. If you are working on Win32 you can actually manipulate the console screen buffer directly.
A good place to start might be here
http://msdn.microsoft.com/en-us/library/ms683171(VS.85).aspx
I have been looking for similar functions/API which would allow me to access the console as something other than a stream of text for other platforms. Haven't found anything yet, but then again, I haven't been looking that hard.
Hope it helps.

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