[binutils-gdb/binutils-2_26-branch] Provide AC_PROG_LEX that copes with LEX=missing from top-level

[Alan Modra <amodra at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=334b860d4e5656348710e45afb0cebca203468eb

commit 334b860d4e5656348710e45afb0cebca203468eb
Author: Alan Modra <amodra@gmail.com>
Date:   Mon Jan 18 16:06:49 2016 +1030

    Provide AC_PROG_LEX that copes with LEX=missing from top-level
    
    config/
    	PR binutils/19481
    	* override.m4 (AC_PROG_LEX): Define.
    binutils/
    	* configure: Regenerate.
    gas/
    	* configure: Regenerate.
    ld/
    	* configure: Regenerate.

Diff:
---
 binutils/ChangeLog |  4 ++++
 binutils/configure |  9 +++++----
 config/ChangeLog   |  5 +++++
 config/override.m4 | 12 ++++++++++++
 gas/ChangeLog      |  4 ++++
 gas/configure      |  9 +++++----
 ld/ChangeLog       |  4 ++++
 ld/configure       |  9 +++++----
 8 files changed, 44 insertions(+), 12 deletions(-)

diff --git a/binutils/ChangeLog b/binutils/ChangeLog
index 73efc3f..6fb2851 100644
--- a/binutils/ChangeLog
+++ b/binutils/ChangeLog
@@ -1,3 +1,7 @@
+2016-01-18  Alan Modra  <amodra@gmail.com>
+
+	* configure: Regenerate.
+
 2015-12-10  Alan Modra  <amodra@gmail.com>
 
 	Apply from master.
diff --git a/binutils/configure b/binutils/configure
index bbabdc6..694857a 100755
--- a/binutils/configure
+++ b/binutils/configure
@@ -12112,8 +12112,9 @@ fi
 done
 test -n "$LEX" || LEX=":"
 
-if test "x$LEX" != "x:"; then
-  cat >conftest.l <<_ACEOF
+case "$LEX" in
+  :|*"missing "*) ;;
+  *) cat >conftest.l <<_ACEOF
 %%
 a { ECHO; }
 b { REJECT; }
@@ -12224,8 +12225,8 @@ $as_echo "#define YYTEXT_POINTER 1" >>confdefs.h
 
 fi
 rm -f conftest.l $LEX_OUTPUT_ROOT.c
-
-fi
+ ;;
+esac
 if test "$LEX" = :; then
   LEX=${am_missing_run}flex
 fi
diff --git a/config/ChangeLog b/config/ChangeLog
index 6847cb9..216aaef 100644
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,3 +1,8 @@
+2016-01-18  Alan Modra  <amodra@gmail.com>
+
+	PR binutils/19481
+	* override.m4 (AC_PROG_LEX): Define.
+
 2015-08-24  Yaakov Selkowitz  <yselkowi@redhat.com>
 
 	* iconv.m4 (AM_ICONV_LINK): Use in-tree libiconv when present.
diff --git a/config/override.m4 b/config/override.m4
index 52bd1c3..b5ce654 100644
--- a/config/override.m4
+++ b/config/override.m4
@@ -101,4 +101,16 @@ m4_define([_AC_CHECK_DECLS],
 
 ])
 
+dnl If flex/lex are not found, the top level configure sets LEX to
+dnl "/path_to/missing flex".  When AC_PROG_LEX tries to find the flex
+dnl output file, it calls $LEX to do so, but the current lightweight
+dnl "missing" won't create a file.  This results in an error.
+dnl Avoid calling the bulk of AC_PROG_LEX when $LEX is "missing".
+AC_DEFUN_ONCE([AC_PROG_LEX],
+[AC_CHECK_PROGS(LEX, flex lex, :)
+case "$LEX" in
+  :|*"missing "*) ;;
+  *) _AC_PROG_LEX_YYTEXT_DECL ;;
+esac])
+
 ])
diff --git a/gas/ChangeLog b/gas/ChangeLog
index 7a4ea43..e37d065 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,7 @@
+2016-01-18  Alan Modra  <amodra@gmail.com>
+
+	* configure: Regenerate.
+
 2015-12-17  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>
 
 	* gas/config/tc-arm.c (aeabi_set_public_attributes): Adjust
diff --git a/gas/configure b/gas/configure
index f2864b7..29c5fb4 100755
--- a/gas/configure
+++ b/gas/configure
@@ -12862,8 +12862,9 @@ fi
 done
 test -n "$LEX" || LEX=":"
 
-if test "x$LEX" != "x:"; then
-  cat >conftest.l <<_ACEOF
+case "$LEX" in
+  :|*"missing "*) ;;
+  *) cat >conftest.l <<_ACEOF
 %%
 a { ECHO; }
 b { REJECT; }
@@ -12974,8 +12975,8 @@ $as_echo "#define YYTEXT_POINTER 1" >>confdefs.h
 
 fi
 rm -f conftest.l $LEX_OUTPUT_ROOT.c
-
-fi
+ ;;
+esac
 if test "$LEX" = :; then
   LEX=${am_missing_run}flex
 fi
diff --git a/ld/ChangeLog b/ld/ChangeLog
index cc7474d..68911b6 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,7 @@
+2016-01-18  Alan Modra  <amodra@gmail.com>
+
+	* configure: Regenerate.
+
 2016-01-11  Kwok Cheung Yeung  <kcy@codesourcery.com>
 
 	PR ld/18199
diff --git a/ld/configure b/ld/configure
index b900175..0638f51 100755
--- a/ld/configure
+++ b/ld/configure
@@ -16130,8 +16130,9 @@ fi
 done
 test -n "$LEX" || LEX=":"
 
-if test "x$LEX" != "x:"; then
-  cat >conftest.l <<_ACEOF
+case "$LEX" in
+  :|*"missing "*) ;;
+  *) cat >conftest.l <<_ACEOF
 %%
 a { ECHO; }
 b { REJECT; }
@@ -16242,8 +16243,8 @@ $as_echo "#define YYTEXT_POINTER 1" >>confdefs.h
 
 fi
 rm -f conftest.l $LEX_OUTPUT_ROOT.c
-
-fi
+ ;;
+esac
 if test "$LEX" = :; then
   LEX=${am_missing_run}flex
 fi