其中 3.0.7：
Fix traits of Map
Fix a few warnings (507) and documentation (531)
3.1.4：
Bug 620: Fix robustness and performance issues in JacobiSVD::solve.
Bug 613: Fix accuracy of SSE sqrt for very small numbers.
Bug 608: Fix sign computation in LDLT.
Fix write access to CwiseUnaryView expressions.
Fix compilation of transposeInPlace() for Array expressions.
Fix non const data() member in Array and Matrix wrappers.
Fix a few warnings and compilation issues with recent compiler versions.
Documentation fixes.
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