[mlir] build fix for gcc-5
authorStephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Fri, 14 Aug 2020 18:26:29 +0000 (11:26 -0700)
committerStephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Fri, 14 Aug 2020 18:39:04 +0000 (11:39 -0700)
commit6ce8e4f46b7aeef9d18580cf1612695a0f409cbb
treea98e8935f8a87705153bb6c81466e329705a09fb
parent324ae458df7ed2b8fa55ddb93af5af17887347a3
[mlir] build fix for gcc-5

It appears in this case that an implicit cast from StringRef to std::string
doesn't happen.  Fixed with an explicit cast.

Differential Revision: https://reviews.llvm.org/D85986
mlir/lib/IR/Dialect.cpp