Fix crash when writing empty graph in NetworkitBinaryWriter #1338
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… by using path.string() (c_str() return wchar_t on Windows.)
angriman
reviewed
Jul 27, 2025
angriman
previously approved these changes
Jul 29, 2025
angriman
approved these changes
Aug 1, 2025
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This PR fixes a crash when writing an empty graph (numberOfNodes() == 0) using NetworkitBinaryWriter.
Closes #909.
Root Cause
When serializing an empty graph, the internal logic attempted to compute offset values based on the number of chunks. However, if nodes == 0, then chunks == 0, and expressions like (chunks - 1) underflowed due to unsigned arithmetic. This led to corrupted headers and potential segmentation faults during read/write operations.
Fix
This PR addresses the issue by: