diff --git a/gcl.spec b/gcl.spec
index 46fec6e..00309a4 100644
--- a/gcl.spec
+++ b/gcl.spec
@@ -1,5 +1,8 @@
-# SGC requires the frame pointer.
-%global __global_cflags %__global_cflags -fno-omit-frame-pointer
+# Address randomization breaks gcl's memory management scheme
+%undefine _hardened_build
+
+# SGC requires the frame pointer, and the sources assume C89 semantics
+%global __global_cflags %__global_cflags -fno-omit-frame-pointer -std=gnu89
 
 Name:           gcl
 Version:        2.6.12
@@ -169,6 +172,9 @@ gcl_exec_t.
 %patch14
 %patch15
 
+# Don't insert line numbers into cmpinclude.h; the compiler gets confused
+sed -i 's,$(CC) -E,& -P,' makefile
+
 # Ensure the frame pointer doesn't get added back
 sed -i 's/"-fomit-frame-pointer"/""/' configure