Fix a build issue from iocore cleanup#12000
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moonchen merged 8 commits intoapache:masterfrom Feb 4, 2025
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The build of test_net was broken on Mac when the build mode is set to release. Root cause: We support two kinds of linkers. One kind will only search for symbols that are to the left of the object being linked. Another kind will search the list of libraries repeatedly until the no new undefined references are created. Both are sensitive to the order of libraries on the command line. In order to work with both, we have to carefully order our dependencies in cmake. See the build rule for traffic_server for a working list of dependencies. In this case, libinknet_stub.cc provides some symbols that are also provided by ts::proxy, in order to fix an issue of cyclic dependency between ts::inknet and ts::proxy. However, this causes the link to have duplicate symbols when libraries are not ordered correctly, on linkers that repeat through the list. References: https://stackoverflow.com/questions/45135/why-does-the-order-in-which-libraries-are-linked-sometimes-cause-errors-in-gcc
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* Fix a build issue from iocore cleanup The build of test_net was broken on Mac when the build mode is set to release. Root cause: We support two kinds of linkers. One kind will only search for symbols that are to the left of the object being linked. Another kind will search the list of libraries repeatedly until the no new undefined references are created. Both are sensitive to the order of libraries on the command line. In order to work with both, we have to carefully order our dependencies in cmake. See the build rule for traffic_server for a working list of dependencies. In this case, libinknet_stub.cc provides some symbols that are also provided by ts::proxy, in order to fix an issue of cyclic dependency between ts::inknet and ts::proxy. However, this causes the link to have duplicate symbols when libraries are not ordered correctly, on linkers that repeat through the list. References: https://stackoverflow.com/questions/45135/why-does-the-order-in-which-libraries-are-linked-sometimes-cause-errors-in-gcc Solution: For ld, use link groups so the linker searches the group repeatedly until symbols are resolved. For other linkers, carefully order the static libraries so the duplicate symbols are resolved before their stubs are seen.
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The build of test_net was broken on Mac when the build mode is set to release.
Root cause:
We support two kinds of linkers. One kind will only search for symbols that are to the left of the object being linked. Another kind will search the list of libraries repeatedly until the no new undefined references are created. Both are sensitive to the order of libraries on the command line.
In order to work with both, we have to carefully order our dependencies in cmake. See the build rule for traffic_server for a working list of dependencies.
In this case, libinknet_stub.cc provides some symbols that are also provided by ts::proxy, in order to fix an issue of cyclic dependency between ts::inknet and ts::proxy. However, this causes the link to have duplicate symbols when libraries are not ordered correctly, on linkers that repeat through the list.
References:
https://stackoverflow.com/questions/45135/why-does-the-order-in-which-libraries-are-linked-sometimes-cause-errors-in-gcc