From: simonpj <unknown>
Date: Mon, 26 Feb 2001 15:41:18 +0000 (+0000)
Subject: [project @ 2001-02-26 15:41:18 by simonpj]
X-Git-Tag: Approximately_9120_patches~2550
X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;h=ecb2ccfb36c2b2b9605082eb6a0b0349ecb7dcfb;p=ghc-hetmet.git

[project @ 2001-02-26 15:41:18 by simonpj]
Dont print generic insts if there arent any
---

diff --git a/ghc/compiler/typecheck/TcInstDcls.lhs b/ghc/compiler/typecheck/TcInstDcls.lhs
index fd70cff..53e30cc 100644
--- a/ghc/compiler/typecheck/TcInstDcls.lhs
+++ b/ghc/compiler/typecheck/TcInstDcls.lhs
@@ -312,6 +312,9 @@ getGenericInstances class_decls
     let
 	gen_inst_info = concat gen_inst_infos
     in
+    if null gen_inst_info then
+	returnTc []
+    else
     getDOptsTc						`thenTc`  \ dflags ->
     ioToTc (dumpIfSet_dyn dflags Opt_D_dump_deriv "Generic instances" 
 		      (vcat (map pprInstInfo gen_inst_info)))