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XOpenDisplay segfaults if passed invalid display name

The following simple test case always segfaults:

#include <X11/Xlib.h>

int main(void) {
    XOpenDisplay("this is invalid");
    return 0;
}

Backtrace:

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7cd80a6 in pthread_cond_destroy@@GLIBC_2.3.2 () from /usr/lib/libc.so.6
(gdb) bt
#0  0x00007ffff7cd80a6 in pthread_cond_destroy@@GLIBC_2.3.2 () from /usr/lib/libc.so.6
#1  0x00007ffff7e97b1f in _XFreeX11XCBStructure () from /usr/lib/libX11.so.6
#2  0x00007ffff7e8745f in _XFreeDisplayStructure () from /usr/lib/libX11.so.6
#3  0x00007ffff7e87e82 in XOpenDisplay () from /usr/lib/libX11.so.6
#4  0x000055555555514c in main ()

Environment:

  • Arch Linux (x86_64)
  • libx11 1.7.4-1
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