Add variable named PLATFORMLIBDL to control OS-specific usage of libdl.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6752 91177308-0d34-0410-b5e6-96231b3b80d8

Makefile.FreeBSD

@@ -22,6 +22,9 @@ PLATFORMLINKOPTS := -Wl,--export-dynamic
 # stripped from the resultant binary.
 PLATFORMSTRIPOPTS := -Wl,-x
 
+# PLATFORMLIBDL - FreeBSD does not have libdl; dlsym() is in libc.
+PLATFORMLIBDL := 
+
 # Path to location for LLVM front-end for this architecture.  This setting may
 # be overriden by the Makefile.config option, and should not override it if set.
 # (Using Linux GCC front-end for now.)

Makefile.Linux

@@ -22,6 +22,9 @@ PLATFORMLINKOPTS := -Wl,--export-dynamic
 # stripped from the resultant binary.
 PLATFORMSTRIPOPTS := -Wl,-x
 
+# PLATFORMLIBDL - Library that supports dlsym() et al. 
+PLATFORMLIBDL := -ldl
+
 # Path to location for LLVM front-end for this architecture.  This setting may
 # be overriden by the Makefile.config option, and should not override it if set.
 #

Makefile.SunOS

@@ -24,6 +24,9 @@ PLATFORMLINKOPTS := -lmalloc
 #
 PLATFORMSTRIPOPTS :=
 
+# PLATFORMLIBDL - Library that supports dlsym() et al. 
+PLATFORMLIBDL := -ldl
+
 # Path to location for LLVM front-end for this architecture.  This setting may
 # be overriden by the Makefile.config option, and should not override it if set.
 #