Ignore --export-dynamic if --relocatable is given

[ruiu]

Summary

The combination of the two flags doesn't make sense, and other linkers
seem to just ignore --export-dynamic if --relocatable is given. This
patch makes lld compatible with that behavior.

Fixes https://bugs.llvm.org/show_bug.cgi?id=43552

[ruiu]

• report error instead of ignoring -export-dynamic

[grimar]

LGTM with 2 nits.

lld/test/ELF/driver.test

54 ↗

(On Diff #223793)

Remove this duplication.

77 ↗

(On Diff #223793)

-o %tfail -> -o /dev/null

[ruiu]

lld/test/ELF/driver.test

77 ↗

(On Diff #223793)

I'll do that in a follow-up patch to replace all occurrences of %tfail in this file in one shot.

lld/trunk/ELF/Driver.cpp

if (config->relocatable) {
     if (config->gcSections)
       error("-r and --gc-sections may not be used together");
     if (config->gdbIndex)
       error("-r and --gdb-index may not be used together");
     if (config->icf != ICFLevel::None)
       error("-r and --icf may not be used together");
     if (config->pie)
       error("-r and -pie may not be used together");
+    if (config->exportDynamic)
+      error("-r and --export-dynamic may not be used together");
   }
 
   if (config->executeOnly) {
     if (config->emachine != EM_AARCH64)
       error("-execute-only is only supported on AArch64 targets");
 
     if (config->singleRoRx && !script->hasSectionsCommand)
       error("-execute-only and -no-rosegment cannot be used together");

lld/trunk/test/ELF/driver.test

 # ERR10: unknown -z value: foo
 
 ## Check we report "unknown -z value" error even with -v.
 # RUN: not ld.lld %t -z foo -v 2>&1 | FileCheck -check-prefix=ERR10 %s
 
 # RUN: not ld.lld %t -z max-page-size 2>&1 | FileCheck -check-prefix=ERR11 %s
 # ERR11: unknown -z value: max-page-size
 
+## Attempt to use -r and --export-dynamic together
+# RUN: not ld.lld -r -export-dynamic %t -o %tfail 2>&1 | FileCheck -check-prefix=ERR12 %s
+# ERR12: -r and --export-dynamic may not be used together
+
 .globl _start
 _start:
   nop

lld/trunk/test/ELF/lto/relocation-model.ll

 ; REQUIRES: x86
 
 ; RUN: llvm-as %s -o %t.o
 ; RUN: llvm-as %p/Inputs/relocation-model-pic.ll -o %t.pic.o
 
 ;; Non-PIC source.
 
 ; RUN: ld.lld %t.o -o %t-out -save-temps -shared
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
 
 ; RUN: ld.lld %t.o -o %t-out -save-temps --export-dynamic --noinhibit-exec -pie
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
 
 ; RUN: ld.lld %t.o -o %t-out -save-temps --export-dynamic --noinhibit-exec
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC
 
-; RUN: ld.lld %t.o -o %t-out -save-temps -r --export-dynamic
-; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC
-
 
 ;; PIC source.
 
 ; RUN: ld.lld %t.pic.o -o %t-out -save-temps -shared
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
 
 ; RUN: ld.lld %t.pic.o -o %t-out -save-temps --export-dynamic --noinhibit-exec -pie
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
 
 ; RUN: ld.lld %t.pic.o -o %t-out -save-temps --export-dynamic --noinhibit-exec
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC
 
-; RUN: ld.lld %t.pic.o -o %t-out -save-temps -r --export-dynamic
-; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
-
 
 ;; Explicit flag.
 
 ; RUN: ld.lld %t.o -o %t-out -save-temps -r -mllvm -relocation-model=pic
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
 
 ; RUN: ld.lld %t.o -o %t-out -save-temps -r -mllvm -relocation-model=static
 ; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC