- Welcome to Pelles C forum.
Pelles C forum
News:
Download Pelles C here: http://www.pellesc.se
Recent posts
#21
Tips & tricks / Re: Silly test for msvcrt and ...
Last post by jack - February 08, 2026, 01:34:15 PMQuote from: TimoVJL on February 08, 2026, 01:12:09 PMA that <options> is a local storage ?that is my guess
#22
Tips & tricks / Re: Silly test for msvcrt and ...
Last post by TimoVJL - February 08, 2026, 01:12:09 PMA that <options> is a local storage ?
Code Select
#if _CRT_FUNCTIONS_REQUIRED
// This function must not be inlined into callers to avoid ODR violations. The
// static local variable has different names in C and in C++ translation units.
_Check_return_ _Ret_notnull_
_CRT_INLINE_PURE_SECURITYCRITICAL_ATTRIBUTE
__declspec(noinline) __inline unsigned __int64* __CRTDECL __local_stdio_printf_options(void)
{
static unsigned __int64 _OptionsStorage;
return &_OptionsStorage;
}
// This function must not be inlined into callers to avoid ODR violations. The
// static local variable has different names in C and in C++ translation units.
_Check_return_ _Ret_notnull_
_CRT_INLINE_PURE_SECURITYCRITICAL_ATTRIBUTE
__declspec(noinline) __inline unsigned __int64* __CRTDECL __local_stdio_scanf_options(void)
{
static unsigned __int64 _OptionsStorage;
return &_OptionsStorage;
}
#endif
#if defined _M_CEE && !defined _M_CEE_PURE
#pragma managed(pop)
#endif
#define _CRT_INTERNAL_LOCAL_PRINTF_OPTIONS (*__local_stdio_printf_options())
#define _CRT_INTERNAL_LOCAL_SCANF_OPTIONS (*__local_stdio_scanf_options ())
#define _CRT_INTERNAL_PRINTF_LEGACY_VSPRINTF_NULL_TERMINATION (1ULL << 0)
#define _CRT_INTERNAL_PRINTF_STANDARD_SNPRINTF_BEHAVIOR (1ULL << 1)
#define _CRT_INTERNAL_PRINTF_LEGACY_WIDE_SPECIFIERS (1ULL << 2)
#define _CRT_INTERNAL_PRINTF_LEGACY_MSVCRT_COMPATIBILITY (1ULL << 3)
#define _CRT_INTERNAL_PRINTF_LEGACY_THREE_DIGIT_EXPONENTS (1ULL << 4)
#define _CRT_INTERNAL_PRINTF_STANDARD_ROUNDING (1ULL << 5)
#define _CRT_INTERNAL_SCANF_SECURECRT (1ULL << 0)
#define _CRT_INTERNAL_SCANF_LEGACY_WIDE_SPECIFIERS (1ULL << 1)
#define _CRT_INTERNAL_SCANF_LEGACY_MSVCRT_COMPATIBILITY (1ULL << 2)
Code Select
// CRT headers are included into some kinds of source files where only data type
// definitions and macro definitions are required but function declarations and
// inline function definitions are not. These files include assembly files, IDL
// files, and resource files. The tools that process these files often have a
// limited ability to process C and C++ code. The _CRT_FUNCTIONS_REQUIRED macro
// is defined to 1 when we are compiling a file that actually needs functions to
// be declared (and defined, where applicable), and to 0 when we are compiling a
// file that does not. This allows us to suppress declarations and definitions
// that are not compilable with the aforementioned tools.
#if !defined _CRT_FUNCTIONS_REQUIRED
#if defined __assembler || defined __midl || defined RC_INVOKED
#define _CRT_FUNCTIONS_REQUIRED 0
#else
#define _CRT_FUNCTIONS_REQUIRED 1
#endif
#endif
#23
Tips & tricks / Re: Silly test for msvcrt and ...
Last post by jack - February 08, 2026, 12:52:41 PM@TimoVJL I am back early
trying to link against ucrt with Pelles C is not straightforward but it easy using llvm-mingw gcc from https://github.com/mstorsjo/llvm-mingw/releases
using the 64-bit version I compiled the following code: gcc sprintf-timing.c -o sprintf-timing
sprintf-timing.c
I ran the following from the msys2 shell
objdump.exe -d -M intel,x86-64 sprintf-timing.exe >sprintf-timing.txt
and then searched the disassembly for stdio_common_vsprintf, here are the relevant pieces
the only missing piece of the puzzle is 140005048 <options>
trying to link against ucrt with Pelles C is not straightforward but it easy using llvm-mingw gcc from https://github.com/mstorsjo/llvm-mingw/releases
using the 64-bit version I compiled the following code: gcc sprintf-timing.c -o sprintf-timing
sprintf-timing.c
Code Select
#include <stdio.h>
#include <windows.h>
#define ITERATIONS 1000000
int main() {
SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_TIME_CRITICAL);
char buffer[256];
LARGE_INTEGER frequency, start, end;
double x=1.2345678901234567890;
double total_time = 0;
QueryPerformanceFrequency(&frequency);
for (int i = 0; i < ITERATIONS; i++) {
QueryPerformanceCounter(&start);
sprintf(buffer, "%.15g", x);
QueryPerformanceCounter(&end);
total_time += (double)(end.QuadPart - start.QuadPart) / frequency.QuadPart;
}
printf("Average sprintf time: %.2f nanoseconds\n",
(total_time / ITERATIONS) * 1e9);
}
as you mentioned to Vortex, ucrtbase does not provide a straight printf or sprintf but it does provide stdio_common_vfprintf and stdio_common_vsprintfI ran the following from the msys2 shell
objdump.exe -d -M intel,x86-64 sprintf-timing.exe >sprintf-timing.txt
and then searched the disassembly for stdio_common_vsprintf, here are the relevant pieces
Code Select
0000000140001f30 <printf>:
140001f30: 56 push rsi
140001f31: 57 push rdi
140001f32: 48 83 ec 38 sub rsp,0x38
140001f36: 48 89 ce mov rsi,rcx
140001f39: 48 89 54 24 58 mov QWORD PTR [rsp+0x58],rdx
140001f3e: 4c 89 44 24 60 mov QWORD PTR [rsp+0x60],r8
140001f43: 4c 89 4c 24 68 mov QWORD PTR [rsp+0x68],r9
140001f48: 48 8d 44 24 58 lea rax,[rsp+0x58]
140001f4d: 48 89 44 24 30 mov QWORD PTR [rsp+0x30],rax
140001f52: e8 99 07 00 00 call 1400026f0 <__local_stdio_printf_options>
140001f57: 48 8b 38 mov rdi,QWORD PTR [rax]
140001f5a: b9 01 00 00 00 mov ecx,0x1
140001f5f: e8 ac 07 00 00 call 140002710 <__acrt_iob_func>
140001f64: 48 8b 4c 24 30 mov rcx,QWORD PTR [rsp+0x30]
140001f69: 48 89 4c 24 20 mov QWORD PTR [rsp+0x20],rcx
140001f6e: 48 89 f9 mov rcx,rdi
140001f71: 48 89 c2 mov rdx,rax
140001f74: 49 89 f0 mov r8,rsi
140001f77: 45 31 c9 xor r9d,r9d
140001f7a: e8 c1 09 00 00 call 140002940 <__stdio_common_vfprintf>
140001f7f: 90 nop
140001f80: 48 83 c4 38 add rsp,0x38
140001f84: 5f pop rdi
140001f85: 5e pop rsi
140001f86: c3 ret
140001f87: cc int3
140001f88: cc int3
140001f89: cc int3
140001f8a: cc int3
140001f8b: cc int3
140001f8c: cc int3
140001f8d: cc int3
140001f8e: cc int3
140001f8f: cc int3
0000000140001f90 <sprintf>:
140001f90: 56 push rsi
140001f91: 57 push rdi
140001f92: 48 83 ec 38 sub rsp,0x38
140001f96: 48 89 d6 mov rsi,rdx
140001f99: 48 89 cf mov rdi,rcx
140001f9c: 4c 89 44 24 60 mov QWORD PTR [rsp+0x60],r8
140001fa1: 4c 89 4c 24 68 mov QWORD PTR [rsp+0x68],r9
140001fa6: 48 8d 44 24 60 lea rax,[rsp+0x60]
140001fab: 48 89 44 24 30 mov QWORD PTR [rsp+0x30],rax
140001fb0: e8 3b 07 00 00 call 1400026f0 <__local_stdio_printf_options>
140001fb5: 48 8b 08 mov rcx,QWORD PTR [rax]
140001fb8: 48 83 c9 02 or rcx,0x2
140001fbc: 48 8b 44 24 30 mov rax,QWORD PTR [rsp+0x30]
140001fc1: 48 89 44 24 28 mov QWORD PTR [rsp+0x28],rax
140001fc6: 48 c7 44 24 20 00 00 mov QWORD PTR [rsp+0x20],0x0
140001fcd: 00 00
140001fcf: 48 89 fa mov rdx,rdi
140001fd2: 49 c7 c0 ff ff ff ff mov r8,0xffffffffffffffff
140001fd9: 49 89 f1 mov r9,rsi
140001fdc: e8 6f 09 00 00 call 140002950 <__stdio_common_vsprintf>
140001fe1: 90 nop
140001fe2: 48 83 c4 38 add rsp,0x38
140001fe6: 5f pop rdi
140001fe7: 5e pop rsi
140001fe8: c3 ret
140001fe9: cc int3
140001fea: cc int3
140001feb: cc int3
140001fec: cc int3
140001fed: cc int3
140001fee: cc int3
140001fef: cc int3
00000001400026f0 <__local_stdio_printf_options>:
1400026f0: 48 8d 05 51 29 00 00 lea rax,[rip+0x2951] # 140005048 <options>
1400026f7: c3 ret
1400026f8: cc int3
1400026f9: cc int3
1400026fa: cc int3
1400026fb: cc int3
1400026fc: cc int3
1400026fd: cc int3
1400026fe: cc int3
1400026ff: cc int3
the only missing piece of the puzzle is 140005048 <options>
#24
Tips & tricks / Re: Silly test for msvcrt and ...
Last post by jack - February 06, 2026, 11:33:32 PMwill give a good test Monday, I am off to visit my family and won't be back till Monday
#25
Tips & tricks / Re: Silly test for msvcrt and ...
Last post by jack - February 06, 2026, 10:32:07 PMthanks TimoVJL 👍
#26
Tips & tricks / Silly test for msvcrt and ucrt...
Last post by TimoVJL - February 06, 2026, 11:28:10 AM #27
Announcements / Re: New Year, new URL
Last post by Vortex - February 05, 2026, 07:40:06 PMHi Timo,
It looks like that here is the issue :
It looks like that here is the issue :
Code Select
PWORD pMenu = pPtr;
if (*(WORD*)pPtr) { // Menu ?
---------> while (pPtr) pPtr++; <-------------- This line
pPtr ++; // past zero
} else {
pPtr ++;
} #28
Bug reports / Re: tchar.h: Missing Macro _pu...
Last post by Pelle - February 05, 2026, 05:55:12 PMOK. Anyway, should be added now for the next version. Best guess: first release candidate at beginning of next month.
#29
Bug reports / Re: tchar.h: Missing Macro _pu...
Last post by Fuerst - February 04, 2026, 10:46:17 PMThe technology helps me to maintain a console program that determines and outputs metadata for files (including file names containing non-ASCII characters) under both Windows and UNIX/Linux.
#30
Announcements / Re: New Year, new URL
Last post by Vortex - February 04, 2026, 09:57:39 PMHi Timo,
I built your code as a 32-bit console application but it crashes on Windows 7 64-bit.
I built your code as a 32-bit console application but it crashes on Windows 7 64-bit.
Code Select
ResDlgConv3.exe Rsrc.res
CRT: unhandled exception (main) -- terminating