28 lines
1.1 KiB
ReStructuredText
28 lines
1.1 KiB
ReStructuredText
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.. title:: clang-tidy - bugprone-dynamic-static-initializers
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bugprone-dynamic-static-initializers
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====================================
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Finds instances of static variables that are dynamically initialized
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in header files.
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This can pose problems in certain multithreaded contexts. For example,
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when disabling compiler generated synchronization instructions for
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static variables initialized at runtime (e.g. by ``-fno-threadsafe-statics``), even if a particular project
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takes the necessary precautions to prevent race conditions during
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initialization by providing their own synchronization, header files included from other projects may
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not. Therefore, such a check is helpful for ensuring that disabling
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compiler generated synchronization for static variable initialization will not cause
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problems.
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Consider the following code:
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.. code-block:: c
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int foo() {
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static int k = bar();
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return k;
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}
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When synchronization of static initialization is disabled, if two threads both call `foo` for the first time, there is the possibility that `k` will be double initialized, creating a race condition.
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