[PATCH] D36874: [ELF] - Mention "-z notext" and -fPIC in some error messages

[Rui Ueyama via Phabricator via llvm-commits]

ruiu added inline comments.


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Comment at: test/ELF/dynamic-reloc-in-ro.s:5-10
+// CHECK:      can't create dynamic relocation R_X86_64_64 against local symbol in readonly segment
+// CHECK-NEXT: >>> defined in {{.*}}.o
+// CHECK-NEXT: >>> referenced by {{.*}}.o:(.text+0x0)
+// CHECK-NEXT: >>> Usually this error happens when -fPIC flag is missing during compilation.
+// CHECK-NEXT: >>> Unintentional use of such relocations is undesirable, and not
+// CHECK-NEXT: >>> permited by default, consider using -z notext.
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This error message style is not desirable, as two list elements ("defined in ..." and "referenced by ..." and the description text "Usually ..." are in the same list. That is just like this

  Found an error
   - at file foo.c
   - on line 100
   - Usually this error happens when you made a mistake blah blah

and I believe you can see why this is wrong.

I also wonder if you really want to mention `-z notext`. We want to recommend or endorse the option because we want to avoid text relocations in general. In most cases, you just need to compile object files with -fPIC, so I believe you want to mention only that.

Overall, I'd change the message to "can't create dynamic relocation R_X86_64_64 against local symbol in readonly segment; recompile object files with -fPIC to fix this error".


https://reviews.llvm.org/D36874