[ELF] Improve error message for incompatible section flags

Previously we were not printing out the flags of the incompatible
section which made it difficult to determine what the problem was.

The error message format has been change to the following:

  error: incompatible section flags for .bar
  >>> /foo/bar/incompatible-section-flags.s.tmp.o:(.bar): 0x403
  >>> output section .bar: 0x3

Patch by Alexander Richardson.

Differential Revision: https://reviews.llvm.org/D32484

llvm-svn: 301319

diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index a40818d..71fc00a 100644 (file)
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -405,8 +405,10 @@ void OutputSectionFactory::addInputSec(InputSectionBase *IS,
   OutputSection *&Sec = Map[Key];
   if (Sec) {
     if (getIncompatibleFlags(Sec->Flags) != getIncompatibleFlags(IS->Flags))
-      error("Section has flags incompatible with others with the same name " +
-            toString(IS));
+      error("incompatible section flags for " + Sec->Name +
+            "\n>>> " + toString(IS) + ": 0x" + utohexstr(IS->Flags) +
+            "\n>>> output section " + Sec->Name + ": 0x" +
+            utohexstr(Sec->Flags));
     if (Sec->Type != IS->Type) {
       if (canMergeToProgbits(Sec->Type) && canMergeToProgbits(IS->Type))
         Sec->Type = SHT_PROGBITS;

diff --git a/lld/test/ELF/incompatible-section-flags.s b/lld/test/ELF/incompatible-section-flags.s
index efca31b..25d9994 100644 (file)
--- a/lld/test/ELF/incompatible-section-flags.s
+++ b/lld/test/ELF/incompatible-section-flags.s
@@ -1,8 +1,13 @@
 // RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 // RUN: not ld.lld -shared %t.o -o %t 2>&1 | FileCheck %s
 
-// CHECK: error:  Section has flags incompatible with others with the same name {{.*}}incompatible-section-flags.s.tmp.o:(.foo)
-// CHECK: error:  Section has flags incompatible with others with the same name {{.*}}incompatible-section-flags.s.tmp.o:(.bar)
+// CHECK:      error: incompatible section flags for .foo
+// CHECK-NEXT: >>> {{.*}}incompatible-section-flags.s.tmp.o:(.foo): 0x3
+// CHECK-NEXT: >>> output section .foo: 0x403
+
+// CHECK:      error: incompatible section flags for .bar
+// CHECK-NEXT: >>> {{.*}}incompatible-section-flags.s.tmp.o:(.bar): 0x403
+// CHECK-NEXT: >>> output section .bar: 0x3
 
 .section .foo, "awT", @progbits, unique, 1
 .quad 0