[version] bump gcc and a few others to v6.1.0
diff --git a/toolvers b/toolvers
index dd54846..7b776a1 100644
--- a/toolvers
+++ b/toolvers
@@ -1,14 +1,14 @@
 # Rerun updatetoolvers after modifying this file
-GCCVER=5.3.0
+GCCVER=6.1.0
 BINVER=2.26
-GDBVER=7.10.1
+GDBVER=7.11
 GMPVER=5.1.3
 MPCVER=1.0.3
-MPFRVER=3.1.3
+MPFRVER=3.1.4
 # Below is autogenerated by updatetoolvers
-GCCHASH=b84f5592e9218b73dbae612b5253035a7b34a9a1f7688d2e1bfaaf7267d5c4db
+GCCHASH=09c4c85cabebb971b1de732a0219609f93fc0af5f86f6e437fd8d7f832f1a351
 BINHASH=c2ace41809542f5237afc7e3b8f32bb92bc7bc53c6232a84463c423b0714ecd9
-GDBHASH=25c72f3d41c7c8554d61cacbeacd5f40993276d2ccdec43279ac546e3993d6d5
+GDBHASH=7a434116cb630d77bb40776e8f5d3937bed11dea56bafebb4d2bc5dd389fe5c1
 GMPHASH=752079520b4690531171d0f4532e40f08600215feefede70b24fabdc6f1ab160
 MPCHASH=617decc6ea09889fb08ede330917a00b16809b8db88c29c31bfbb49cbf88ecc3
-MPFRHASH=f63bb459157cacd223caac545cb816bcdb5a0de28b809e7748b82e9eb89b0afd
+MPFRHASH=d3103a80cdad2407ed581f3618c4bed04e0c92d1cf771a65ead662cc397f7775