overloaded virtual function rewrite was hidden error during build

I'm trying to build using Option 1, but the build fails when building several of the targets, including RegionConversions.cpp.o where the error is

```FAILED: tools/Imex/lib/Dialect/Region/Transforms/CMakeFiles/obj.IMEXRegionTransforms.dir/RegionConversions.cpp.o
/usr/bin/c++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/elliott/software/intel-mlir/llvm-project/build/tools/Imex/lib/Dialect/Region/Transforms -I/home/elliott/software/intel-mlir/mlir-extensions/lib/Dialect/Region/Transforms -I/home/elliott/software/intel-mlir/llvm-project/build/include -I/home/elliott/software/intel-mlir/llvm-project/llvm/include -I/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include -I/home/elliott/software/intel-mlir/llvm-project/build/tools/mlir/include -I/home/elliott/software/intel-mlir/mlir-extensions/include -I/home/elliott/software/intel-mlir/llvm-project/build/tools/Imex/include -Wno-error -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -fno-lifetime-dse -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-maybe-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -Wall -Werror -Wnon-virtual-dtor -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -fno-lifetime-dse -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-maybe-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++17 -D_GNU_SOURCE -D_DEBUG -D_GLIBCXX_ASSERTIONS -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT tools/Imex/lib/Dialect/Region/Transforms/CMakeFiles/obj.IMEXRegionTransforms.dir/RegionConversions.cpp.o -MF tools/Imex/lib/Dialect/Region/Transforms/CMakeFiles/obj.IMEXRegionTransforms.dir/RegionConversions.cpp.o.d -o tools/Imex/lib/Dialect/Region/Transforms/CMakeFiles/obj.IMEXRegionTransforms.dir/RegionConversions.cpp.o -c /home/elliott/software/intel-mlir/mlir-extensions/lib/Dialect/Region/Transforms/RegionConversions.cpp
In file included from /home/elliott/software/intel-mlir/mlir-extensions/include/imex/Dialect/Region/IR/RegionOps.h:22,
from /home/elliott/software/intel-mlir/mlir-extensions/lib/Dialect/Region/Transforms/RegionConversions.cpp:15:
/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include/mlir/Transforms/DialectConversion.h: In instantiation of ‘class mlir::OpConversionPattern’:
/home/elliott/software/intel-mlir/mlir-extensions/lib/Dialect/Region/Transforms/RegionConversions.cpp:25:22: required from here
25 | : public ::mlir::OpConversionPattern<::imex::region::EnvironmentRegionOp> {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include/mlir/IR/PatternMatch.h:255:16: error: ‘virtual void mlir::RewritePattern::rewrite(mlir::Operation*, mlir::PatternRewriter&) const’ was hidden [-Werror=overloaded-virtual=]
255 | virtual void rewrite(Operation *op, PatternRewriter &rewriter) const;
| ^~~~~~~
In file included from /home/elliott/software/intel-mlir/mlir-extensions/lib/Dialect/Region/Transforms/RegionConversions.cpp:16:
/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include/mlir/Transforms/DialectConversion.h:669:16: note: by ‘mlir::OpConversionPattern::rewrite’
669 | virtual void rewrite(SourceOp op, OneToNOpAdaptor adaptor,
| ^~~~~~~
/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include/mlir/Transforms/DialectConversion.h: In instantiation of ‘class mlir::OpConversionPattern’:
/home/elliott/software/intel-mlir/mlir-extensions/lib/Dialect/Region/Transforms/RegionConversions.cpp:65:22: required from here
65 | : public ::mlir::OpConversionPattern {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include/mlir/IR/PatternMatch.h:255:16: error: ‘virtual void mlir::RewritePattern::rewrite(mlir::Operation*, mlir::PatternRewriter&) const’ was hidden [-Werror=overloaded-virtual=]
255 | virtual void rewrite(Operation *op, PatternRewriter &rewriter) const;
| ^~~~~~~
/home/elliott/software/intel-mlir/llvm-project/llvm/../mlir/include/mlir/Transforms/DialectConversion.h:669:16: note: by ‘mlir::OpConversionPattern::rewrite’
669 | virtual void rewrite(SourceOp op, OneToNOpAdaptor adaptor,
| ^~~~~~~
cc1plus: all warnings being treated as errors
[3516/3790] Building CXX object tools/Imex/lib/Dialect/NDArray/IR/CMakeFiles/obj.IMEXNDArrayDialect.dir/NDArrayOps.cpp.o
ninja: build stopped: subcommand failed.
```

I've tried building on a couple different systems, but I get the same error and wasn't able to find a workaround yet. Am I building incorrectly?