Recent posts

#11

General discussion / Re: Pelles C and Windows Defen...

Last post by Pelle - April 18, 2026, 06:04:49 PM

Is it because Pelles C binaries are not signed? If yes, why?

Probably. Last time I checked the price for a certificate to be trusted was for a company wallet, not a personal one.

#12

Bug reports / Re: Some fonts are missing fro...

Last post by Pelle - April 18, 2026, 05:58:35 PM

I am deliberately filtering the fonts list. At least last time I checked, several years ago, not doing this filtering gave me many fonts I couldn't use.
I will have to think about this (when I can find the time)...

#13

Bug reports / Re: Maybe a optimization bug.

Last post by Pelle - April 18, 2026, 05:52:29 PM

But seriously yes there have been, and are issues, with using the optimizations and extensive testing is always needed for these.  I have many programs using optimizations successfully.

I my experience, enabling the optimizer on poorly written C code is more of a problem than the optimizer itself.

#14

Bug reports / Re: Maybe a optimization bug.

Last post by Pelle - April 18, 2026, 05:48:32 PM

A sanity check is missing in the loop idiom optimizer: triangular numbers. This affects all targets. We'll see when I can fix this...

/* The triangular numbers are given by the following formula:
 * Tn = 1 + 2 + 3 + .. + n = (n * (n + 1)) / 2
 */

#15

Bug reports / Re: Maybe a optimization bug.

Last post by Vortex - April 16, 2026, 09:13:41 PM

Disassembling the 32-bit MS COFF object module, building the project as 32-bit console application :

Code Select Expand

_text   SEGMENT PARA PUBLIC 'CODE'

_main   PROC NEAR
        push    eax
        push    offset @152
        call    _printf                               
        add     esp, 8     
        push    5050                                   
        push    offset @154                           
        call    _printf                               
        add     esp, 8                                 
        xor     eax, eax                               
        ret                                           
_main   ENDP

.rdata  SEGMENT DWORD PUBLIC 'CONST'               

@154    label byte
        db 73H, 75H, 6DH, 3DH, 25H, 64H, 0AH, 00H       ; 0000 _ sum=%d..

@152    label byte
        db 69H, 3DH, 25H, 64H, 0AH, 00H                 ; 0008 _ i=%d..

.rdata  ENDS

#16

Bug reports / Re: Maybe a optimization bug.

Last post by TimoVJL - April 16, 2026, 06:04:07 PM

It might be a cdecl problem, so 32-bit programs can use stdcall to avoid it.

#17

Bug reports / Re: Maybe a optimization bug.

Last post by Vortex - April 15, 2026, 10:00:46 PM

The trick i=i-(-1); seems to solve the issue :

Code Select Expand

#include <stdio.h>

int main(void)
{
int i=1, sum=0;
while (i<=100)
{
sum=sum+i;
//i++;
i=i-(-1);
}
printf("i=%d\n",i);
printf("sum=%d\n",sum);
return 0;
}


#18

Bug reports / Re: Maybe a optimization bug.

Last post by John Z - April 15, 2026, 01:57:27 PM

By the way, uncommenting the line below will output the correct result :

Very typical in my experience for the optimization failures.  Sometimes even just a 1 byte change can make it work, or make it fail.

John Z

#19

Add-ins / Re: Line Counter Add-IN

Last post by John Z - April 15, 2026, 01:48:16 PM

Updated DLL for Pelles C Version 14.  No code changes, up-sized the menu icon

John Z

#20

Bug reports / Re: Maybe a optimization bug.

Last post by TimoVJL - April 15, 2026, 12:35:08 PM

For all bug hunters, use pope.exe to check obj-file, as it have internal disassembler.