More descriptive error for dynamic-pointer

* libguile/dynl.c (sysdep_dynl_value): Failure to find a symbol is not
  an error, so raise our own, more appropriate error.

* test-suite/tests/foreign.test ("dynamic-pointer"): Add a test.

1 files changed, 2 insertions, 3 deletions

diff --git a/libguile/dynl.c b/libguile/dynl.c
index 2484ddaa0..a2ae6e267 100644
--- a/libguile/dynl.c
+++ b/libguile/dynl.c
@@ -115,9 +115,8 @@ sysdep_dynl_value (const char *symb, void *handle, const char *subr)
 
   fptr = lt_dlsym ((lt_dlhandle) handle, symb);
   if (!fptr)
-    {
-      scm_misc_error (subr, (char *) lt_dlerror (), SCM_EOL);
-    }
+    scm_misc_error (subr, "Symbol not found: ~a",
+                    scm_list_1 (scm_from_locale_string (symb)));
   return fptr;
 }