URL: <http://savannah.gnu.org/support/?109320>
Summary: _AC_PROG_LEX_YYTEXT_DECL fails to compute LEXLIB correctly using the original AT&T lex if Xcode's flex is installed Project: Autoconf Submitted by: None Submitted on: Tue 23 May 2017 01:04:53 AM UTC Category: None Priority: 5 - Normal Severity: 3 - Normal Status: None Privacy: Public Assigned to: None Originator Email: t...@ojodeagua.com Open/Closed: Open Discussion Lock: Any Operating System: Mac OS _______________________________________________________ Details: Mac OS installs flex (obsolete version 2.5.35) as a part of Xcode's command line tools, with it's library installed as /usr/lib/libl.a. I have a copy of a more recent flex (version 2.6.1) installed in /usr/local/bin, with its library installed as /usr/local/lib/libfl.a. I also have a copy of the 4.3BSD version of lex installed in /usr/local/bin, with it's library installed as /usr/local/lib/libl.a. I have a package that I want to be able to build with either lex or flex. If I force AC_PROG_LEX to use lex rather than flex when running configure, the AC_LINK_IFELSE test located in _AC_PROG_LEX_YYTEXT_DECL fails for all choices ('', -lfl, -ll) but the AC_PROG_LEX macro completes with output message "none needed" (and with LEXLIB empty). It took me a bit of head scratching until I understood what was happening: The loop running AC_LINK_IFELSE is not distinguishing between termination with success ("break" out of the loop) and termination with failure (normal completion of the loop). The AC_LINK_IFELSE fails when I force the use of lex because it tries to use the (incorrectly named) 'flex' link library /usr/lib/libl.a, since the default library search path is /usr/lib then /usr/local/lib. I can, of course, work around this defect in _AC_PROG_LEX_YYTEXT_DECL by setting LDFLAGS="-L/usr/local/lib" on the configure command line. However, it would have been nice if configure pointed out my error explicitly. I have attached a patch to the file "programs.m4" _______________________________________________________ File Attachments: ------------------------------------------------------- Date: Tue 23 May 2017 01:04:53 AM UTC Name: programs.m4.patch Size: 979B By: None <http://savannah.gnu.org/support/download.php?file_id=40765> _______________________________________________________ Reply to this item at: <http://savannah.gnu.org/support/?109320> _______________________________________________ Message sent via/by Savannah http://savannah.gnu.org/