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digitalmars.D - how to find stack trace of "Error: 4invalid UTF-8 sequence" "Error: std.format int argument expected"?

reply nobody <no where.com> writes:
dmd v1.045 on Linux, I got error like:

Error: 4invalid UTF-8 sequence
Error: std.format int argument expected

Then I run the program under debugger, there is no indication where the error
occurred:

Error: 4invalid UTF-8 sequence

Program exited with code 01.
(gdb) where
No stack.

This is ridiculous: why cannot the library generate segfault instead?
May 27 2009
next sibling parent reply Jarrett Billingsley <jarrett.billingsley gmail.com> writes:
On Wed, May 27, 2009 at 11:13 PM, nobody <no where.com> wrote:
 dmd v1.045 on Linux, I got error like:

 Error: 4invalid UTF-8 sequence
 Error: std.format int argument expected

 Then I run the program under debugger, there is no indication where the error
 occurred:

 Error: 4invalid UTF-8 sequence

 Program exited with code 01.
 (gdb) where
 No stack.

 This is ridiculous: why cannot the library generate segfault instead?

Lol, because segfaults aren't a real method of indicating errors. From what I understand, you can set GDB to break whenever _d_throw is called. I don't know the syntax. If you don't want to use a debugger, there's always printf/writefln/Stdout debugging. Then you can find out what data is causing the unicode transcoding methods to barf.
May 27 2009
parent reply nobody <no where.com> writes:
 From what I understand, you can set GDB to break whenever _d_throw is
 called.  I don't know the syntax.

Thanks for the hint. I googled it, here's the way to do it: $ objdump -x your.exe | grep throw 0819c1e0 g F .text 00000217 _d_throw 4 (gdb) break *0x0819c1e0 Breakpoint 1 at 0x819c1e0 (gdb) r ... (gdb) where #0 0x0819c1e0 in _d_throw 4 () #1 0x081b397c in _D3std6format8doFormatFDFwZvAC8TypeInfoPvZv10getFmtStarMFZi () #2 0x081b2207 in _D3std6format8doFormatFDFwZvAC8TypeInfoPvZv () #3 0x081b19c9 in _D3std5stdio7writefxFPS3std1c5stdio6_iobufAC8TypeInfoPviZv () #4 0x081b1ac4 in _D3std5stdio6writefFYv ()
 If you don't want to use a debugger, there's always
 printf/writefln/Stdout debugging.

using writefln to find writefln errors? ;-)
May 27 2009
parent Leandro Lucarella <llucax gmail.com> writes:
nobody, el 28 de mayo a las 04:08 me escribiste:
 From what I understand, you can set GDB to break whenever _d_throw is
 called.  I don't know the syntax.

Thanks for the hint. I googled it, here's the way to do it: $ objdump -x your.exe | grep throw 0819c1e0 g F .text 00000217 _d_throw 4 (gdb) break *0x0819c1e0 Breakpoint 1 at 0x819c1e0 (gdb) r ... (gdb) where #0 0x0819c1e0 in _d_throw 4 () #1 0x081b397c in _D3std6format8doFormatFDFwZvAC8TypeInfoPvZv10getFmtStarMFZi () #2 0x081b2207 in _D3std6format8doFormatFDFwZvAC8TypeInfoPvZv () #3 0x081b19c9 in _D3std5stdio7writefxFPS3std1c5stdio6_iobufAC8TypeInfoPviZv () #4 0x081b1ac4 in _D3std5stdio6writefFYv ()
 If you don't want to use a debugger, there's always
 printf/writefln/Stdout debugging.

using writefln to find writefln errors? ;-)

When debugging C++, the stack trace shows the exact point where the exception was thrown, so there is a way to get this right in D, I just don't know how =) -- Leandro Lucarella (luca) | Blog colectivo: http://www.mazziblog.com.ar/blog/ ---------------------------------------------------------------------------- GPG Key: 5F5A8D05 (F8CD F9A7 BF00 5431 4145 104C 949E BFB6 5F5A 8D05) ----------------------------------------------------------------------------
May 28 2009
prev sibling parent Jarrett Billingsley <jarrett.billingsley gmail.com> writes:
On Thu, May 28, 2009 at 12:08 AM, nobody <no where.com> wrote:

 If you don't want to use a debugger, there's always
 printf/writefln/Stdout debugging.

using writefln to find writefln errors? ;-)

As long as you don't use invalid UTF-8 data in your debugging statements ;)
May 27 2009