void-packages/srcpkgs/freecad/patches/002-execinfo.patch

--- src/App/Application.cpp	2018-04-06 10:48:37.000000000 +0200
+++ src/App/Application.cpp	2018-04-22 15:04:11.876136151 +0200
@@ -1063,7 +1063,9 @@
 #endif
 
 #if defined(FC_OS_LINUX)
+#ifdef __GLIBC__
 #include <execinfo.h>
+#endif
 #include <dlfcn.h>
 #include <cxxabi.h>
 
@@ -1075,6 +1077,7 @@
 // This function produces a stack backtrace with demangled function & method names.
 void printBacktrace(size_t skip=0)
 {
+#ifdef __GLIBC__
     void *callstack[128];
     size_t nMaxFrames = sizeof(callstack) / sizeof(callstack[0]);
     size_t nFrames = backtrace(callstack, nMaxFrames);
@@ -1105,6 +1108,9 @@
     }
 
     free(symbols);
+#else
+    std::cerr << "sorry, no backtrace on musl libc";
+#endif
 }
 #endif