fbc4ba4b4e
At some point in the past few years, binutils became more aggressive at removing unused symbols. To function as a symbol requirement, a relocation record must now be in a section marked with @progbits and must not be in a section which gets discarded during the link (either via --gc-sections or via /DISCARD/). Update REQUIRE_SYMBOL() to generate relocation records meeting these criteria. To minimise the impact upon the final binary size, we use existing symbols (specified via the REQUIRING_SYMBOL() macro) as the relocation targets where possible. We use R_386_NONE or R_X86_64_NONE relocation types to prevent any actual unwanted relocation taking place. Where no suitable symbol exists for REQUIRING_SYMBOL() (such as in config.c), the macro PROVIDE_REQUIRING_SYMBOL() can be used to generate a one-byte-long symbol to act as the relocation target. If there are versions of binutils for which this approach fails, then the fallback will probably involve killing off REQUEST_SYMBOL(), redefining REQUIRE_SYMBOL() to use the current definition of REQUEST_SYMBOL(), and postprocessing the linked ELF file with something along the lines of "nm -u | wc -l" to check that there are no undefined symbols remaining. Signed-off-by: Michael Brown <mcb30@ipxe.org> |
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| .. | ||
| 80211 | ||
| infiniband | ||
| oncrpc | ||
| tcp | ||
| udp | ||
| aoe.c | ||
| arp.c | ||
| dhcpopts.c | ||
| dhcppkt.c | ||
| eapol.c | ||
| eth_slow.c | ||
| ethernet.c | ||
| fakedhcp.c | ||
| fc.c | ||
| fcels.c | ||
| fcns.c | ||
| fcoe.c | ||
| fcp.c | ||
| fragment.c | ||
| icmp.c | ||
| icmpv4.c | ||
| icmpv6.c | ||
| infiniband.c | ||
| iobpad.c | ||
| ipv4.c | ||
| ipv6.c | ||
| ndp.c | ||
| neighbour.c | ||
| netdev_settings.c | ||
| netdevice.c | ||
| nullnet.c | ||
| ping.c | ||
| rarp.c | ||
| retry.c | ||
| rndis.c | ||
| socket.c | ||
| tcp.c | ||
| tcpip.c | ||
| tls.c | ||
| udp.c | ||
| validator.c | ||
| vlan.c | ||