mirror of https://github.com/ipxe/ipxe.git
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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| .. | ||
| axtls | ||
| aes_wrap.c | ||
| arc4.c | ||
| asn1.c | ||
| axtls_aes.c | ||
| bigint.c | ||
| cbc.c | ||
| certstore.c | ||
| chap.c | ||
| cms.c | ||
| crc32.c | ||
| crypto_null.c | ||
| deflate.c | ||
| drbg.c | ||
| entropy.c | ||
| hash_df.c | ||
| hmac.c | ||
| hmac_drbg.c | ||
| md5.c | ||
| null_entropy.c | ||
| ocsp.c | ||
| privkey.c | ||
| random_nz.c | ||
| rbg.c | ||
| rootcert.c | ||
| rsa.c | ||
| sha1.c | ||
| sha1extra.c | ||
| sha256.c | ||
| x509.c | ||