[Lint] Add check to prevent usage of #include <regex>

Currently, the pytorch wheels available through `pip install` use the
pre-C++11 ABI by setting `-DUSE_CXX11_ABI=0` [0].  If TVM were to user
the pre-C++11 ABI, this would cause breakages with dynamically-linked
LLVM environments.

This commit adds a lint check to search for use of `#include <regex>`
in any C++ files.  Use of this header should be avoided, as its
implementation is not supported by gcc's dual ABI.  This ABI
incompatibility results in runtime errors either when `std::regex` is
called from TVM, or when `std::regex` is called from pytorch,
depending on which library was loaded first.

This restriction can be removed when a version of pytorch compiled
using `-DUSE_CXX11_ABI=1` is available from PyPI.

[0] pytorch/pytorch#51039

Author: Lunderberg

tests/lint/cpplint.sh

@@ -28,3 +28,13 @@ python3 3rdparty/dmlc-core/scripts/lint.py --quiet tvm cpp \
 			"src/runtime/hexagon/rpc/hexagon_rpc_skel.c" \
 			"src/runtime/hexagon/rpc/hexagon_rpc_stub.c" \
 			"src/relay/backend/contrib/libtorch/libtorch_codegen.cc"
+
+
+if find src -name "*.cc" -exec grep -Hn '^#include <regex>$' {} +; then
+    echo "The <regex> header file may not be used in TVM," 1>&2
+    echo "because it causes ABI incompatibility with most pytorch installations." 1>&2
+    echo "Pytorch packages on PyPI currently set `-DUSE_CXX11_ABI=0`," 1>&2
+    echo "which causes ABI compatibility when calling <regex> functions." 1>&2
+    echo "See https://github.com/pytorch/pytorch/issues/51039 for more details." 1>&2
+    exit 1
+fi