#16174: GhcEnableTablesNextToCode=NO breaks NCG on macOS -------------------------------------+------------------------------------- Reporter: angerman | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.6.2 Component: Compiler | Version: 8.6.3 (CodeGen) | Keywords: NCG, TNCT, | Operating System: Unknown/Multiple TablesNextToCode | Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- It appears as if `GhcEnableTablesNextToCode=NO` breaks the NCG on macOS as early as GHC 8.4. Running the following {{{ git reset --hard HEAD git clean -xfd git submodule update --init --recursive git clean -xfd sed -E "s/^#BuildFlavour[ ]+= quick-cross$/BuildFlavour = quick/" < mk/build.mk.sample > mk/build.mk echo "GhcEnableTablesNextToCode=NO" >> mk/build.mk ./boot && ./configure --silent && make -s -j9 }}} on macOS with the 8.4 and 8.6 generated duplicate symbols in the assembly file. Something like {{{ .text .align 3 Lc4l: Lc4l: jmp Lc4u .const_data .align 3 .align 0 _Lc4l_info: .quad Lc4l .quad 259 .long 30 .long 0 }}} which causes the assembler to choke. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16174 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler