From: Jim Wilson Date: Thu, 17 Oct 2019 22:38:27 +0000 (-0700) Subject: RISC-V: Report unresolved relocation error via linker's callback function. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=330a6637a53d4b6694c9f8fa04155d4366453621;p=binutils-gdb.git RISC-V: Report unresolved relocation error via linker's callback function. Two patches from Nelson Chu. It is better to use the linker's callback functions to handle the link time error when relocating. The unresolved relocation error can be regarded as an unsupported relocation. To make user easier to understand different errors, we need to extend the current error message format of the callback function since the format is fixed. bfd/ * elfnn-riscv.c (riscv_elf_relocate_section): Use asprintf to extend the error message if needed, and then store the result into the `msg_buf`. Finally, remember to free the unused `msg_buf`. All error message for the dangerous relocation should be set before we call the callback function. If we miss the error message since linker runs out of memory, we should set the default error message for the error. ld/ * testsuite/ld-riscv-elf/lib-nopic-01a.s: Create the shared library lib-nopic-01a.so, it will be linked with lib-nopic-01b.s. * testsuite/ld-riscv-elf/lib-nopic-01b.s: Add new test for the unresolved relocation. Link the non-pic code into a shared library may cause the error. * testsuite/ld-riscv-elf/lib-nopic-01b.d: Likewise. * testsuite/ld-riscv-elf/ld-riscv-elf.exp: Run the new test only when the shared library is supported. R_RISCV_CALL, R_RISCV_JAL and R_RISCV_RVC_JUMP are pc-relative relocation. For now, we do not allow the object with these relocation links into a shared library since the referenced symbols may be loaded to the places that too far from the pc. We can improve the error message for these unsupported relocation to notice user that they should recompile their code with `fPIC`. bfd/ * elfnn-riscv.c (riscv_elf_relocate_section): Report the error message that user should recompile their code with `fPIC` when linking non-pic code into shared library. ld/ * testsuite/ld-riscv-elf/lib-nopic-01b.d: Update the error message. Change-Id: Ib3347a0a6fa1c2b20a9647c314d5bec2c322ff04 --- diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 74cdda4ffaa..b29b2ee98d1 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,16 @@ +2019-10-17 Nelson Chu + + * elfnn-riscv.c (riscv_elf_relocate_section): Report the error message + that user should recompile their code with `fPIC` when linking non-pic + code into shared library. + + * elfnn-riscv.c (riscv_elf_relocate_section): Use asprintf to extend + the error message if needed, and then store the result into the + `msg_buf`. Finally, remember to free the unused `msg_buf`. All error + message for the dangerous relocation should be set before we call the + callback function. If we miss the error message since linker runs out + of memory, we should set the default error message for the error. + 2019-10-16 Alan Modra PR 13616 diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c index 4ffe6a36e68..6be209e2398 100644 --- a/bfd/elfnn-riscv.c +++ b/bfd/elfnn-riscv.c @@ -1787,6 +1787,7 @@ riscv_elf_relocate_section (bfd *output_bfd, int r_type = ELFNN_R_TYPE (rel->r_info), tls_type; reloc_howto_type *howto = riscv_elf_rtype_to_howto (input_bfd, r_type); const char *msg = NULL; + char *msg_buf = NULL; bfd_boolean resolved_to_zero; if (howto == NULL @@ -2088,6 +2089,7 @@ riscv_elf_relocate_section (bfd *output_bfd, || (h != NULL && h->type == STT_SECTION)) && rel->r_addend) { + msg = _("%pcrel_lo section symbol with an addend"); r = bfd_reloc_dangerous; break; } @@ -2302,24 +2304,42 @@ riscv_elf_relocate_section (bfd *output_bfd, && _bfd_elf_section_offset (output_bfd, info, input_section, rel->r_offset) != (bfd_vma) -1) { - (*_bfd_error_handler) - (_("%pB(%pA+%#" PRIx64 "): " - "unresolvable %s relocation against symbol `%s'"), - input_bfd, - input_section, - (uint64_t) rel->r_offset, - howto->name, - h->root.root.string); - - bfd_set_error (bfd_error_bad_value); - ret = FALSE; - goto out; + switch (r_type) + { + case R_RISCV_CALL: + case R_RISCV_JAL: + case R_RISCV_RVC_JUMP: + if (asprintf (&msg_buf, + _("%%X%%P: relocation %s against `%s' can " + "not be used when making a shared object; " + "recompile with -fPIC\n"), + howto->name, + h->root.root.string) == -1) + msg_buf = NULL; + break; + + default: + if (asprintf (&msg_buf, + _("%%X%%P: unresolvable %s relocation against " + "symbol `%s'\n"), + howto->name, + h->root.root.string) == -1) + msg_buf = NULL; + break; + } + + msg = msg_buf; + r = bfd_reloc_notsupported; } if (r == bfd_reloc_ok) r = perform_relocation (howto, rel, relocation, input_section, input_bfd, contents); + /* We should have already detected the error and set message before. + If the error message isn't set since the linker runs out of memory + or we don't set it before, then we should set the default message + with the "internal error" string here. */ switch (r) { case bfd_reloc_ok: @@ -2338,17 +2358,21 @@ riscv_elf_relocate_section (bfd *output_bfd, break; case bfd_reloc_outofrange: - msg = _("%X%P: internal error: out of range error\n"); + if (msg == NULL) + msg = _("%X%P: internal error: out of range error\n"); break; case bfd_reloc_notsupported: - msg = _("%X%P: internal error: unsupported relocation error\n"); + if (msg == NULL) + msg = _("%X%P: internal error: unsupported relocation error\n"); break; case bfd_reloc_dangerous: + /* The error message should already be set. */ + if (msg == NULL) + msg = _("dangerous relocation error"); info->callbacks->reloc_dangerous - (info, "%pcrel_lo section symbol with an addend", input_bfd, - input_section, rel->r_offset); + (info, msg, input_bfd, input_section, rel->r_offset); break; default: @@ -2356,9 +2380,14 @@ riscv_elf_relocate_section (bfd *output_bfd, break; } - if (msg) + /* Do not report error message for the dangerous relocation again. */ + if (msg && r != bfd_reloc_dangerous) info->callbacks->einfo (msg); + /* Free the unused `msg_buf` if needed. */ + if (msg_buf) + free (msg_buf); + /* We already reported the error via a callback, so don't try to report it again by returning false. That leads to spurious errors. */ ret = TRUE; diff --git a/ld/ChangeLog b/ld/ChangeLog index f51e6466e68..8fc2ceee9d0 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,16 @@ +2019-10-17 Nelson Chu + + * testsuite/ld-riscv-elf/lib-nopic-01b.d: Update the error message. + + * testsuite/ld-riscv-elf/lib-nopic-01a.s: Create the shared library + lib-nopic-01a.so, it will be linked with lib-nopic-01b.s. + * testsuite/ld-riscv-elf/lib-nopic-01b.s: Add new test for the + unresolved relocation. Link the non-pic code into a shared library + may cause the error. + * testsuite/ld-riscv-elf/lib-nopic-01b.d: Likewise. + * testsuite/ld-riscv-elf/ld-riscv-elf.exp: Run the new test only when + the shared library is supported. + 2019-10-16 Alan Modra PR 13616 diff --git a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp index c994a57c48a..0a7ac5945e8 100644 --- a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp +++ b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp @@ -71,4 +71,11 @@ if [istarget "riscv*-*-*"] { [list "readelf --syms gp-test.sd"] \ "gp-test-${abi}"]] } + + run_ld_link_tests { + { "Link non-pic code into a shared library (setup)" + "-shared" "" "" {lib-nopic-01a.s} + {} "lib-nopic-01a.so" } + } + run_dump_test "lib-nopic-01b" } diff --git a/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s b/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s new file mode 100644 index 00000000000..c95cda05d24 --- /dev/null +++ b/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s @@ -0,0 +1,9 @@ + .option nopic + .text + .align 1 + .globl func1 + .type func1, @function +func1: + call func2 + jr ra + .size func1, .-func1 diff --git a/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d new file mode 100644 index 00000000000..0d758a40d60 --- /dev/null +++ b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d @@ -0,0 +1,5 @@ +#name: link non-pic code into a shared library +#source: lib-nopic-01b.s +#as: +#ld: -shared tmpdir/lib-nopic-01a.so +#error: .*relocation R_RISCV_CALL against `func1' can not be used when making a shared object; recompile with -fPIC diff --git a/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s new file mode 100644 index 00000000000..97fe1374e4f --- /dev/null +++ b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s @@ -0,0 +1,9 @@ + .option nopic + .text + .align 1 + .globl func2 + .type func2, @function +func2: + call func1 + jr ra + .size func2, .-func2