Hello Harithamma, Harithamma D wrote: > I am porting m4 to z/OS and came across following compilation error related > to gnulib: > > In file included from ./builtin.c:25: > In file included from ./m4.h:50: > ../lib/obstack.h:229:8: error: unknown attribute '_Noreturn' ignored > [-Werror,-Wunknown-attributes] > extern __attribute_noreturn__ void (*obstack_alloc_failed_handler) (void); > ^ > ../lib/obstack.h:156:50: note: expanded from macro '__attribute_noreturn__' > # define __attribute_noreturn__ __attribute__ ((__noreturn__)) > ^ > /usr/include/le/features.h:791:26: note: expanded from macro '__noreturn__' > #define __noreturn__ _Noreturn > > > The compile command used is: > > source='builtin.c' object='builtin.o' libtool=no \ > DEPDIR=.deps depmode=hp2 /bin/sh ../build-aux/depcomp \ > xlclang -I../lib -I../lib -DNSIG=42 -D_XOPEN_SOURCE=600 -D_ALL_SOURCE > -D_OPEN_SYS_FILE_EXT=1 -D_AE_BIMODAL=1 -D_ENHANCED_ASCII_EXT=0xFFFFFFFF > -fanalyzer -fno-common -Wall -Wbad-function-cast -Wdate-time > -Wdisabled-optimization -Wdouble-promotion -Wextra -Winit-self -Winline > -Winvalid-pch -Wmissing-declarations -Wmissing-include-dirs > -Wmissing-prototypes -Wnested-externs -Wnull-dereference > -Wold-style-definition -Woverlength-strings -Wpacked -Wpointer-arith -Wshadow > -Wstack-protector -Wstrict-overflow -Wstrict-prototypes -Wuninitialized > -Wunknown-pragmas -Wvariadic-macros -Wwrite-strings -Wformat=2 > -Wno-missing-field-initializers -Werror -qascii -std=gnu11 -qnocsect > -qenum=int -qgonumber -O3 -std=c11 -fgnu89-inline > -I/home/haritha/code/m4port/m4/lib > -I/home/haritha/code/m4port/patches/PR1/include -c -o builtin.o builtin.c > > The above error got fixed when I added the ! defined (__MVS__) condition as > shown in diff file attached. > I would like to upstream these changes. Please let me know if you have any > concerns or questions.
Before doing that: Since xlclang is, AFAIU, a copy of clang modified by IBM, and clang supports __attribute__((__noreturn__)), see https://clang.llvm.org/docs/AttributeReference.html#id20 , it would be more future-oriented if xlclang would support this attribute. Can you please check with the relevant people in your company whether this is a possible course of action? I would prefer to deal with this in Gnulib only if the answer is "no". Bruno
