[flang] [llvm] [clang-tools-extra] [clang] [flang] Add EXECUTE_COMMAND_LINE runtime and lowering intrinsics implementation (PR #74077)

[Yi Wu via cfe-commits]

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@@ -173,5 +173,72 @@ RT_API_ATTRS void ShallowCopy(const Descriptor &to, const Descriptor &from) {
   ShallowCopy(to, from, to.IsContiguous(), from.IsContiguous());
 }
 
+RT_API_ATTRS const char *EnsureNullTerminated(
+    const char *str, std::size_t length, Terminator &terminator) {
+  const void *nullTerminatorPos{std::memchr(str, '\0', length)};
+
+  if (nullTerminatorPos == nullptr) {
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yi-wu-arm wrote:

done

https://github.com/llvm/llvm-project/pull/74077