assembly in future C standard HCF Gerry Wheeler

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  • 1. Memory Leak / Corruption
    Dear All Is the Root Cause of the Memory corruption is the Memory leak, ?? suppose If in the code there is Memory leak, Do this may lead to the Memory Corruption while executing the program ? In nut shell, what is/are the realtion/s between the Memory Leak and Memory Corruption. Juts Theoritical Assumtion below: Ideally Memory leak, may not lead to the Memory Corruption. Here I am talking, if Memory leak Is accepted. Thnaks In Advance. Ranjeet
  • 2. what's wrong with my dummy code?
    hi there! I just wrote a function that reverse a string. It seems all ok to me, but the program goes on segmentation fault on *s = *t_str. Here's the code: #include <stdio.h> #include <stdlib.h> void reverse(char *s) { char t; char* t_str; for (t_str = s; *t_str != '\0'; t_str++); t_str--; for (; s < t_str; s++, t_str--) { t = *s; *s = *t_str; *t_str = t; } } int main(int argc, char *argv[]) { char* s = "Hello world!"; reverse(s); printf("%s", s); return 0; } what's wrong??! thanks! -- Shya,
  • 3. Difference between return and exit
    Hello, I was wondering, what's the difference between exit and return in the main() function? For me they both look the same, or aren't they? And if they aren't, which should I use in which situation? Also I was wondering if it whould be wise to combine the standard status with return. exp: int main(){ printf("Hello World\n"); return EXIT_SUCCESS; } Greetz, Noud Aldenhoven
  • 4. reading an excel file in C?
    Hi All, I want to know,How can one read an Excel file into C,cell by cell? Further I want to compare 2 excel files,cell by cell. I know a crude way which is not working. I can open an xls file and read it character by character untill a '\t'(TAB).Then again read it char by char. I think this should work since an Excel file is nothing but a tab seperated strings.Am I correct? What can be an elegant way? Thanks, -Siliconwafer

Re: assembly in future C standard HCF Gerry Wheeler

Postby Walter Banks » Sat, 04 Nov 2006 22:35:39 GMT

As this thread wanders off topic this industry was introduced to a new
mnemonic in Byte article about decoding the undocumented
Motorola 6800 instructions. The HCF (Halt Catch Fire) opcode $DD
or $D9. HFC locked up the processor and cycled the address bus
The author of that article was Gerry Wheeler.

Gerry Wheeler, 54, died October 15, 2006, advanced non-Hodgkins
lymphoma cancer. Gerry made significant contributions to the technology
of the embedded systems world and was a key part of the development
of many household name products.

Programmer, Ham KG4NBB, author, father, husband, active commuity
participant Gerry will be missed by all.

w..


Similar Threads:

1.assembly in future C standard

Peter Nilsson < XXXX@XXXXX.COM > wrote:

(Crossposted to comp.std.c, with followups directed there, hopefully
 appropriately.  The original post discussed the possibility of whether
 __asm or something similar to it would be added to the C standard.)

> Contrary to Richard Heathfield's categorical statement, it is not an
> absolute given that there will never be an asm keyword in C. But it
> is unlikely because it's already clear that the asm keyword in C++ has
> not served to truly standardise the syntax of inline assembly.

One idea that was not mentioned in the original thread (I imagine for
good reason, because it's a half-baked and probably stupid idea that
occurred to me reading your post) would be to allow for some kind of
conditional assembly, just perhaps something like

#pragma assemble
#pragma X86 /* Inner pragma's implementation-defined */
  /* Inline assembly, which the implementation can ignore or not */
#pragma no-assemble
  /* Stock C code for implementations that can't or won't accept the
   * assemble pragma: */
  for( i=1; i < 10; i++ ) {
    foo();
    /* ... */
  }
#pragma end-assemble

The end result would be something like "If the implementation attempts
to inline the assembly code contained within a #pragma assemble
directive, the behavior is implementation-defined.  Otherwise the
assembly code shall be ignored and the C code contained within any
corresponding #pragma no-assemble directive shall be compiled as
though no directives were present."  It would require adding some
duties to the #pragma directive, but it would allow implementors to
take a reasonable shot at using targetted assembly instructions when
appropriate and available, and reverting to ordinary C otherwise.

I'm sure there are reasons why this is stupid and/or impossible, or it
would have been done already :-)

> At the end of the day, the committee could probably spend many man
> weeks deciding issues on an __asm keyword, but for what? Most
> implementations will keep their existing syntax, and most programmers
> who use inline assembly will no doubt continue to prefer the localised
> syntax because it's less cumbersome than any standard syntax.

Indeed, but it's an interesting thought experiment to consider how the
committee *might* add assembly to C if they chose to do so.  (Well,
interesting to me, at least.)

-- 
C. Benson Manica           | I *should* know what I'm talking about - if I
cbmanica(at)gmail.com      | don't, I need to know.  Flames welcome.



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