search for: an_expression_with_to

LLD treats any symbol referenced from a linker script as a GC root, which makes sense. Unfortunately, it also processes --defsym as a linker script fragment internally, so all target symbols of a --defsym also get treated as GC roots (i.e., if you have something like --defsym SRC=TGT, TGT will become a GC root). I believe this to be unnecessary for defsym specifically, since you're just

...xt_bar is retained > % ld.bfd a.o --defsym d=1 --gc-sections -o a => Neither .text_foo nor > .text_bar is retained > % ld.bfd a.o --defsym c=foo --defsym d=1 --gc-sections -o a => Neither > .text_foo nor .text_bar is retained; lld will retain .text_foo. > > For --defsym from=an_expression_with_to, GNU ld appears to add a > reference from 'from' to 'to'. lld's behavior > (https://reviews.llvm.org/D34195) is more conservative. > > If we stop treating script->referencedSymbols as GC roots, > instructions like `movabs $d, %rax` will no longer be able to acc...

...--gc-sections -o a => Neither .text_foo nor > > .text_bar is retained > > % ld.bfd a.o --defsym c=foo --defsym d=1 --gc-sections -o a => > Neither > > .text_foo nor .text_bar is retained; lld will retain .text_foo. > > > > For --defsym from=an_expression_with_to, GNU ld appears to add a > > reference from 'from' to 'to'. lld's behavior > > ( > https://urldefense.proofpoint.com/v2/url?u=https-3A__reviews.llvm.org_D34195&d=DwIFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MpiPCWMhZJFZg0s-e1l...