configure: WARNING: /usr/bin/indent does not appear to be GNU indent.
scanflags.c:65:13: warning: incompatible integer to pointer conversion passing 'long' to parameter of type 'const char *' [-Wint-conversion]
            (long)sizeof(scanflags_t));
            ^~~~~~~~~~~~~~~~~~~~~~~~~
./flexdef.h:912:60: note: passing argument to parameter here
extern void lerrsf_fatal PROTO ((const char *, const char *));
                                                           ^
1 warning generated.
main.c:1581:5: warning: add explicit braces to avoid dangling else [-Wdangling-else]
                         else
                         ^
1 warning generated.
buf.c:101:60: warning: assigning to 'char *' from 'const char *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
    for (dst = t + sprintf (t, "#line %d \"", lineno), src = filename; *src; *dst++ = *src++)
                                                           ^ ~~~~~~~~
1 warning generated.
Undefined symbols for architecture x86_64:
  "_yylex", referenced from:
      _main in libmain.o
ld: symbol(s) not found for architecture x86_64
Undefined symbols for architecture x86_64:
  "_yylex", referenced from:
      _main in libmain.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [libfl_pic.la] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: *** [libfl.la] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2
flex/2.5.39: WARN: Build folder is dirty, removing it: /Users/jenkins/w/cci_PR-3873@3/.conan/data/flex/2.5.39/_/_/build/1b3a3bedf5a61f5cef16b907ea0b6f9cd93042cb
flex/2.5.39: ERROR: Package '1b3a3bedf5a61f5cef16b907ea0b6f9cd93042cb' build failed
flex/2.5.39: WARN: Build folder /Users/jenkins/w/cci_PR-3873@3/.conan/data/flex/2.5.39/_/_/build/1b3a3bedf5a61f5cef16b907ea0b6f9cd93042cb
ERROR: flex/2.5.39: Error in build() method, line 66
	autotools.make()
	ConanException: Error 2 while executing make -j8