Index: lld/ELF/Driver.cpp =================================================================== --- lld/ELF/Driver.cpp +++ lld/ELF/Driver.cpp @@ -2243,9 +2243,17 @@ if (!sym) continue; - Symbol *real = addUnusedUndefined(saver().save("__real_" + name)); Symbol *wrap = addUnusedUndefined(saver().save("__wrap_" + name), sym->binding); + + // If there is a reference to __real_ pull in the symbol being wrapped. + // Do this after processing the __wrap_ symbol as that may have referenced + // the __real_ symbol. + StringRef realName = saver().save("__real_" + name); + if (symtab.find(realName)) + addUnusedUndefined(name, sym->binding); + + Symbol *real = addUnusedUndefined(realName); v.push_back({sym, real, wrap}); // We want to tell LTO not to inline symbols to be overwritten Index: lld/test/ELF/wrap-extract-real.ll =================================================================== --- /dev/null +++ lld/test/ELF/wrap-extract-real.ll @@ -0,0 +1,66 @@ +# REQUIRES: x86 +## --wrap=xxx should trigger archive extraction for symbol xxx for references to __real_xxx. + +# RUN: rm -rf %t && split-file %s %t && cd %t +# RUN: llvm-as _start.ll -o _start.o +# RUN: llvm-as _start_ref__real_foo.ll -o _start_ref__real_foo.o +# RUN: llvm-as wrap.ll -o wrap.o +# RUN: llvm-as foo.ll -o foo.o + +## Test when the reference to __real_foo is not in __wrap_foo. +# RUN: ld.lld _start_ref__real_foo.o --start-lib foo.o --end-lib --wrap foo -o %t_real.elf +# RUN: llvm-readelf --symbols %t_real.elf | FileCheck %s --check-prefix=REAL + +# REAL: Symbol table '.symtab' contains 5 entries: +# REAL-NEXT: Value Size Type Bind Vis Ndx Name +# REAL-NEXT: {{.*}} {{.*}} NOTYPE LOCAL DEFAULT UND +# REAL-NEXT: {{.*}} {{.*}} FILE LOCAL DEFAULT ABS ld-temp.o +# REAL-NEXT: {{.*}} {{.*}} FUNC GLOBAL DEFAULT 2 _start +# REAL-NEXT: {{.*}} {{.*}} FUNC WEAK DEFAULT 2 foo +# REAL-NEXT: {{.*}} {{.*}} NOTYPE GLOBAL DEFAULT UND __wrap_foo + +## Test when the reference to __real_foo is in __wrap_foo. +# RUN: ld.lld _start.o --start-lib wrap.o --end-lib --start-lib foo.o --end-lib --wrap foo -o %t_wrap_real.elf +# RUN: llvm-readelf --symbols %t_wrap_real.elf | FileCheck %s --check-prefix=WRAP_REAL + +# WRAP_REAL: Symbol table '.symtab' contains 5 entries: +# WRAP_REAL-NEXT: Value Size Type Bind Vis Ndx Name +# WRAP_REAL-NEXT: {{.*}} {{.*}} NOTYPE LOCAL DEFAULT UND +# WRAP_REAL-NEXT: {{.*}} {{.*}} FILE LOCAL DEFAULT ABS ld-temp.o +# WRAP_REAL-NEXT: {{.*}} {{.*}} FUNC GLOBAL DEFAULT 2 _start +# WRAP_REAL-NEXT: {{.*}} {{.*}} FUNC GLOBAL DEFAULT 2 __wrap_foo +# WRAP_REAL-NEXT: {{.*}} {{.*}} FUNC WEAK DEFAULT 2 foo + +#--- _start.ll +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-elf" +define void @_start() { + ret void +} + +#--- _start_ref__real_foo.ll +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-elf" +define void @_start() { + call void @__real_foo() + ret void +} + +declare void @__real_foo() + +#--- wrap.ll +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-elf" +define void @__wrap_foo() { + call void @__real_foo() + ret void +} + +declare void @__real_foo() + +#--- foo.ll +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-elf" +define void @foo() { + ret void +} Index: lld/test/ELF/wrap-extract-real.s =================================================================== --- /dev/null +++ lld/test/ELF/wrap-extract-real.s @@ -0,0 +1,42 @@ +# REQUIRES: x86 +## --wrap=xxx should trigger archive extraction for symbol xxx for references to __real_xxx. + +# RUN: rm -rf %t && split-file %s %t && cd %t +# RUN: llvm-mc -filetype=obj -triple=x86_64 _start.s -o _start.o +# RUN: llvm-mc -filetype=obj -triple=x86_64 ref__real_foo.s -o ref__real_foo.o +# RUN: llvm-mc -filetype=obj -triple=x86_64 wrap.s -o wrap.o +# RUN: llvm-mc -filetype=obj -triple=x86_64 foo.s -o foo.o + +## Test when the reference to __real_foo is not in __wrap_foo. +# RUN: ld.lld _start.o ref__real_foo.o --start-lib foo.o --end-lib --wrap foo -o %t_real.elf +# RUN: llvm-readelf --symbols %t_real.elf | FileCheck %s --check-prefix=REAL + +# REAL: Symbol table '.symtab' contains 4 entries: +# REAL-NEXT: Value Size Type Bind Vis Ndx Name +# REAL-NEXT: {{.*}} 0 NOTYPE LOCAL DEFAULT UND +# REAL-NEXT: {{.*}} 0 NOTYPE GLOBAL DEFAULT 1 _start +# REAL-NEXT: {{.*}} 0 NOTYPE GLOBAL DEFAULT 1 foo +# REAL-NEXT: {{.*}} 0 NOTYPE GLOBAL DEFAULT UND __wrap_foo + +## Test when the reference to __real_foo is in __wrap_foo. +# RUN: ld.lld _start.o --start-lib wrap.o --end-lib --start-lib foo.o --end-lib --wrap foo -o %t_wrap_real.elf +# RUN: llvm-readelf --symbols %t_wrap_real.elf | FileCheck %s --check-prefix=WRAP_REAL + +# WRAP_REAL: Symbol table '.symtab' contains 4 entries: +# WRAP_REAL-NEXT: Value Size Type Bind Vis Ndx Name +# WRAP_REAL-NEXT: {{.*}} 0 NOTYPE LOCAL DEFAULT UND +# WRAP_REAL-NEXT: {{.*}} 0 NOTYPE GLOBAL DEFAULT 1 _start +# WRAP_REAL-NEXT: {{.*}} 0 NOTYPE GLOBAL DEFAULT 1 __wrap_foo +# WRAP_REAL-NEXT: {{.*}} 0 NOTYPE GLOBAL DEFAULT 1 foo + +#--- _start.s +.global _start; _start:; ret + +#--- ref__real_foo.s +call __real_foo + +#--- wrap.s +.global __wrap_foo; __wrap_foo:; call __real_foo + +#--- foo.s +.global foo; foo:; ret