[flang][TBAA] fix unsafe optional deref after #170908 (#172033) PR #170908 introduced an unconditional dereference of the local target variable name, but in rare cases (I am not sure this can be reproduced without `-mllvm -inline-all` currently), such variable may not have a uniq name on the alloca. For instance, this can happen after a call to a function with TARGET character result is inlined. The alloca is a temp on the caller side, that gets the TARGET attribute in the inlined scope via the result name. GitOrigin-RevId: c14c2561704c0c40983cda25ed952584c802d4bb
Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.
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To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.
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