From 8c0ea25fb4a27d4729aabf73f4c00b912bb0c58d Mon Sep 17 00:00:00 2001 From: Matthew Pickering <matthewtpickering@gmail.com> Date: Sat, 7 Jan 2023 11:11:15 +0000 Subject: [PATCH] Pass -Wl,-no_fixup_chains to ld64 when appropiate Recent versions of MacOS use a version of ld where `-fixup_chains` is on by default. This is incompatible with our usage of `-undefined dynamic_lookup`. Therefore we explicitly disable `fixup-chains` by passing `-no_fixup_chains` to the linker on darwin. This results in a warning of the form: ld: warning: -undefined dynamic_lookup may not work with chained fixups The manual explains the incompatible nature of these two flags: -undefined treatment Specifies how undefined symbols are to be treated. Options are: error, warning, suppress, or dynamic_lookup. The default is error. Note: dynamic_lookup that depends on lazy binding will not work with chained fixups. A relevant ticket is #22429 Here are also a few other links which are relevant to the issue: Official comment: https://developer.apple.com/forums/thread/719961 More relevant links: https://openradar.appspot.com/radar?id=5536824084660224 https://github.com/python/cpython/issues/97524 Note in release notes: https://developer.apple.com/documentation/xcode-release-notes/xcode-13-releas e-notes --- configure.ac | 5 +++++ m4/fp_ld_no_fixup_chains.m4 | 24 ++++++++++++++++++++++++ 2 files changed, 29 insertions(+) create mode 100644 m4/fp_ld_no_fixup_chains.m4 diff --git a/configure.ac b/configure.ac index 846a4e54e723..6c4b6b6f53fb 100644 --- a/configure.ac +++ b/configure.ac @@ -658,6 +658,11 @@ FPTOOLS_SET_C_LD_FLAGS([target],[CONF_CC_OPTS_STAGE1],[CONF_GCC_LINKER_OPTS_STAG FPTOOLS_SET_C_LD_FLAGS([target],[CONF_CC_OPTS_STAGE2],[CONF_GCC_LINKER_OPTS_STAGE2],[CONF_LD_LINKER_OPTS_STAGE2],[CONF_CPP_OPTS_STAGE2]) # Stage 3 won't be supported by cross-compilation +FP_LD_NO_FIXUP_CHAINS([target], [LDFLAGS]) +FP_LD_NO_FIXUP_CHAINS([build], [CONF_GCC_LINKER_OPTS_STAGE0]) +FP_LD_NO_FIXUP_CHAINS([target], [CONF_GCC_LINKER_OPTS_STAGE1]) +FP_LD_NO_FIXUP_CHAINS([target], [CONF_GCC_LINKER_OPTS_STAGE2]) + GHC_LLVM_TARGET_SET_VAR # we intend to pass trough --targets to llvm as is. LLVMTarget_CPP=` echo "$LlvmTarget"` diff --git a/m4/fp_ld_no_fixup_chains.m4 b/m4/fp_ld_no_fixup_chains.m4 new file mode 100644 index 000000000000..1d62fd3b20ec --- /dev/null +++ b/m4/fp_ld_no_fixup_chains.m4 @@ -0,0 +1,24 @@ +# FP_LD_NO_FIXUP_CHAINS +# -------------------- +# See if whether we are using a version of ld64 on darwin platforms which +# requires us to pass -no_fixup_chains +# +# $1 = the platform +# $2 = the name of the linker flags variable when linking with $CC +AC_DEFUN([FP_LD_NO_FIXUP_CHAINS], [ + case $$1 in + *-darwin) + AC_MSG_CHECKING([whether ld64 requires -no_fixup_chains]) + echo 'int main(void) {return 0;}' > conftest.c + if $CC -o conftest.o -Wl,-no_fixup_chains conftest.c > /dev/null 2>&1 + then + $2="-Wl,-no_fixup_chains" + AC_MSG_RESULT([yes]) + else + AC_MSG_RESULT([no]) + fi + rm -f conftest.c conftest.o + ;; + + esac +]) -- GitLab