Fix AbslInternalGetFileMappingHint to obey ABSL_OPTION_USE_INLINE_NAMESPACE#2098
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jwnimmer-tri wants to merge 1 commit into
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Fix AbslInternalGetFileMappingHint to obey ABSL_OPTION_USE_INLINE_NAMESPACE#2098jwnimmer-tri wants to merge 1 commit into
jwnimmer-tri wants to merge 1 commit into
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The purpose of
ABSL_OPTION_USE_INLINE_NAMESPACEis to allow multiple independent copies of abseil-cpp to be linked into the same binary, in different (linker) namespaces. For symbols markedextern "C", we need to manually mangle their names to accomplish the same effect.Abseil provides the
ABSL_INTERNAL_C_SYMBOLmacro for this purpose, but it wasn't used onAbslInternalGetFileMappingHint, leading to symbol conflicts when multiple different copies are linked under the same name.Fix this by annotating
AbslInternalGetFileMappingHintwithABSL_INTERNAL_C_SYMBOL.Note that an alternative solution is also possible: the
AbslInternalGetFileMappingHintappears to be dead code in the open-source export of abseil-cpp. (I assume there is nearby google-internal code that uses it.) Instead of mangling the function name, you could also simply remove this code (declaration and definition) from the github export.