• d-bugmail puremagic.com Sep 14 2006
• d-bugmail puremagic.com Sep 14 2006
• Sean Kelly <sean f4.ca> Sep 14 2006
• d-bugmail puremagic.com Jun 25 2008

d-bugmail puremagic.com writes:

http://d.puremagic.com/issues/show_bug.cgi?id=348

           Summary: string concat in dynamically loaded dll code crashes
                    program
           Product: D
           Version: 0.165
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: major
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: default_357-line yahoo.de


A string concat in a dynamically loaded C linkage function crashes the program
with a SIGSEGV in _d_new (wtf)
Files:
_dll.d_
extern (C) { void test(char[] str) { char[] e=str~"bla"; } }
_test.d_
import std.c.windows.windows;

void main() {
  auto func=cast(void function(char[])) GetProcAddress(LoadLibraryA("dll.dll"),
"test");
  func("Bla bla bla ");
}

On gdcwin 0.19, this crashes with a SIGSEGV trying to access 0x0.
The stack trace is:
#0  0x610c1adb in _d_new ()
#1  0x610c1289 in _d_arraycatn ()
#2  0x610c1214 in test (str={length = 12, ptr = 0x41d00d "Bla bla bla "})
    at dll.d:1
#3  0x00401321 in _Dmain () at quick.d:5
#4  0x004013df in _d_run_main2goFZv ()
#5  0x004014e4 in _d_run_main ()
#6  0x00401363 in main ()


-- 

d-bugmail puremagic.com writes:

http://d.puremagic.com/issues/show_bug.cgi?id=348





------- Comment #1 from default_357-line yahoo.de  2006-09-14 16:09 -------
(In reply to comment #0)
 Files:
 _dll.d_
 extern (C) { void test(char[] str) { char[] e=str~"bla"; } }
 _test.d_


a) dmd generates an access error.
b) Compile the first file into a dll with -Wl,--dll and -shared, and the second
file into an executable normally.


-- 

Sean Kelly <sean f4.ca> writes:

d-bugmail puremagic.com wrote:
 
 A string concat in a dynamically loaded C linkage function crashes the program
 with a SIGSEGV in _d_new (wtf)
 Files:
 _dll.d_
 extern (C) { void test(char[] str) { char[] e=str~"bla"; } }
 _test.d_
 import std.c.windows.windows;
 
 void main() {
   auto func=cast(void function(char[])) GetProcAddress(LoadLibraryA("dll.dll"),
 "test");
   func("Bla bla bla ");
 }


Given the above code, I think this is to be expected.  See this link for 
a description of what must be done to produce a dynamic library in D:

http://www.digitalmars.com/d/dll.html

Basically, you must initialize the D compiler runtime, the garbage 
collector, and call module ctors when the library is loaded.  The 
current method for doing this kind of stinks, but it wouldn't be 
terribly difficult to improve.

d-bugmail puremagic.com writes:

http://d.puremagic.com/issues/show_bug.cgi?id=348


bugzilla digitalmars.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID




------- Comment #3 from bugzilla digitalmars.com  2008-06-25 04:18 -------
Sean is correct. Also, dmd doesn't have flags -Wl,--dll and -shared.


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