diff --git a/pkgs/tools/networking/eggdrop/b34a33255f56bbd2317c26da12d702796d67ed50.patch b/pkgs/tools/networking/eggdrop/b34a33255f56bbd2317c26da12d702796d67ed50.patch
new file mode 100644
index 00000000000..03277838e88
--- /dev/null
+++ b/pkgs/tools/networking/eggdrop/b34a33255f56bbd2317c26da12d702796d67ed50.patch
@@ -0,0 +1,36 @@
+From b34a33255f56bbd2317c26da12d702796d67ed50 Mon Sep 17 00:00:00 2001
+From: Geo Van Osterom <george.vo@alum.rpi.edu>
+Date: Thu, 22 Oct 2015 00:12:42 -0400
+Subject: [PATCH] Fix gcc 5 compile errors
+
+---
+ src/net.c     | 2 +-
+ src/tclhash.c | 2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/net.c b/src/net.c
+index a1937de..c369fda 100644
+--- a/src/net.c
++++ b/src/net.c
+@@ -560,7 +560,7 @@ int open_address_listen(sockname_t *addr)
+ /* Returns a socket number for a listening socket that will accept any
+  * connection -- port # is returned in port
+  */
+-inline int open_listen(int *port)
++extern inline int open_listen(int *port)
+ {
+   int sock;
+   sockname_t name;
+diff --git a/src/tclhash.c b/src/tclhash.c
+index 9729acb..22c3d05 100644
+--- a/src/tclhash.c
++++ b/src/tclhash.c
+@@ -113,7 +113,7 @@ static inline void tcl_bind_list_delete(tcl_bind_list_t *tl)
+   nfree(tl);
+ }
+
+-inline void garbage_collect_tclhash(void)
++extern inline void garbage_collect_tclhash(void)
+ {
+   tcl_bind_list_t *tl, *tl_next, *tl_prev;
+   tcl_bind_mask_t *tm, *tm_next, *tm_prev;
diff --git a/pkgs/tools/networking/eggdrop/default.nix b/pkgs/tools/networking/eggdrop/default.nix
index cf7fb20df68..623b42d6fc1 100644
--- a/pkgs/tools/networking/eggdrop/default.nix
+++ b/pkgs/tools/networking/eggdrop/default.nix
@@ -11,6 +11,11 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ tcl ];
 
+  patches = [
+    # https://github.com/eggheads/eggdrop/issues/123
+    ./b34a33255f56bbd2317c26da12d702796d67ed50.patch
+  ];
+
   preConfigure = ''
     prefix=$out/eggdrop
     mkdir -p $prefix