Index: lld/trunk/ELF/Driver.cpp =================================================================== --- lld/trunk/ELF/Driver.cpp +++ lld/trunk/ELF/Driver.cpp @@ -681,22 +681,33 @@ } template static void readCallGraphsFromObjectFiles() { - auto FindSection = [&](const Symbol *Sym) -> const InputSectionBase * { - warnUnorderableSymbol(Sym); - if (const auto *SymD = dyn_cast(Sym)) - return dyn_cast_or_null(SymD->Section); - return nullptr; - }; - for (auto File : ObjectFiles) { auto *Obj = cast>(File); for (const Elf_CGProfile_Impl &CGPE : Obj->CGProfile) { - const InputSectionBase *FromSB = - FindSection(&Obj->getSymbol(CGPE.cgp_from)); - const InputSectionBase *ToSB = FindSection(&Obj->getSymbol(CGPE.cgp_to)); - if (!FromSB || !ToSB) + auto *FromSym = dyn_cast(&Obj->getSymbol(CGPE.cgp_from)); + auto *ToSym = dyn_cast(&Obj->getSymbol(CGPE.cgp_to)); + if (!FromSym || !ToSym) continue; - Config->CallGraphProfile[{FromSB, ToSB}] += CGPE.cgp_weight; + auto *FromSec = dyn_cast_or_null(FromSym->Section); + auto *ToSec = dyn_cast_or_null(ToSym->Section); + + // The profile from .llvm.call-graph-profile is conceptually affiliated to + // FromSec. Don't warn unorderable symbol if FromSym is not absolute + // (FromSec isn't null) and the section is discarded + // (!FromSec->Repl->Live). + // + // We also don't want to warn when ToSym is undefined or is in a shared + // object (as symbols in shared objects are fixed and unorderable). + // + // The check used here is more relaxed (no warning if either FromSym or + // ToSym is not Defined) for simplicity and there is no compelling reason + // to warn on more cases. + if (!FromSec || FromSec->Repl->Live) { + warnUnorderableSymbol(FromSym); + warnUnorderableSymbol(ToSym); + } + if (FromSec && ToSec) + Config->CallGraphProfile[{FromSec, ToSec}] += CGPE.cgp_weight; } } } Index: lld/trunk/test/ELF/cgprofile-obj-warn.s =================================================================== --- lld/trunk/test/ELF/cgprofile-obj-warn.s +++ lld/trunk/test/ELF/cgprofile-obj-warn.s @@ -27,9 +27,6 @@ .cg_profile poppy, A, 30 # CHECK: unable to order absolute symbol: B -# CHECK: unable to order undefined symbol: adena1 -# CHECK: unable to order undefined symbol: adena2 -# CHECK: unable to order undefined symbol: poppy # RUN: ld.lld %t -o /dev/null \ # RUN: -noinhibit-exec -icf=all --no-warn-symbol-ordering 2>&1 \ Index: lld/trunk/test/ELF/cgprofile-shared-warn.s =================================================================== --- lld/trunk/test/ELF/cgprofile-shared-warn.s +++ lld/trunk/test/ELF/cgprofile-shared-warn.s @@ -3,9 +3,19 @@ # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o # RUN: ld.lld --shared %t.o -o /dev/null 2>&1 | count 0 # RUN: ld.lld -e A --unresolved-symbols=ignore-all %t.o -o /dev/null 2>&1 | count 0 - .section .text.A,"ax",@progbits - .globl A + +# RUN: echo '.globl B; B: ret' | llvm-mc -filetype=obj -triple=x86_64-unknown-linux - -o %t1.o +# RUN: ld.lld --shared %t1.o -o %t1.so +# RUN: ld.lld -e A %t.o %t1.so -o /dev/null 2>&1 | count 0 + +# RUN: ld.lld --gc-sections %t.o %t1.so -o /dev/null 2>&1 | count 0 +.globl _start +_start: + ret + +.section .text.A,"ax",@progbits +.globl A A: - callq B + callq B - .cg_profile A, B, 10 +.cg_profile A, B, 10