[gimp] Bug 711795 - execinfo.h functions need -lexecinfo on NetBSD

[Michael Natterer <mitch src gnome org>]

commit 4ac3967a5dbb5eb70d9f6496c1c91b838fbed7ad
Author: Martin Husemann <martin netbsd org>
Date:   Sun Nov 10 22:17:38 2013 +0100

    Bug 711795 - execinfo.h functions need -lexecinfo on NetBSD
    
    Allow building on NetBSD -current where execinfo.h is present but
    backtrace() and backtrace_symbols() are in -lexecinfo.

 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 6eb0e07..f7645e1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -423,6 +423,7 @@ AC_HEADER_SYS_WAIT
 AC_HEADER_TIME
 
 AC_CHECK_HEADERS(execinfo.h sys/param.h sys/time.h sys/times.h sys/wait.h unistd.h)
+AC_CHECK_FUNCS(backtrace, , AC_CHECK_LIB(execinfo, backtrace))
 
 AC_TYPE_PID_T
 AC_FUNC_VPRINTF