https://bugs.gentoo.org/542252

From 32f0df9835ac15ac17e04be57c368172c3ad1d19 Mon Sep 17 00:00:00 2001
From: Pavel Raiskup <praiskup@redhat.com>
Date: Sun, 4 Oct 2015 21:55:03 +0200
Subject: [PATCH] libtool: mitigate the $sed_quote_subst slowdown

When it is reasonably possible, use shell implementation for
quoting.

References:
http://lists.gnu.org/archive/html/libtool/2015-03/msg00005.html
http://lists.gnu.org/archive/html/libtool/2015-02/msg00000.html
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=20006

* gl/build-aux/funclib.sh (func_quote): New function that can be
used as substitution for '$SED $sed_quote_subst' call.
* build-aux/ltmain.in (func_emit_wrapper): Use func_quote instead
of '$SED $sed_quote_subst'.
(func_mode_link): Likewise.
* NEWS: Document.
* bootstrap: Sync with funclib.sh.
---
 NEWS                    |  3 +++
 bootstrap               | 61 +++++++++++++++++++++++++++++++++++++++++++------
 build-aux/ltmain.in     | 10 ++++----
 gl/build-aux/funclib.sh | 61 +++++++++++++++++++++++++++++++++++++++++++------
 4 files changed, 117 insertions(+), 18 deletions(-)

diff --git a/build-aux/ltmain.in b/build-aux/ltmain.in
index 0c40da0..24acefd 100644
--- a/build-aux/ltmain.in
+++ b/build-aux/ltmain.in
@@ -3346,7 +3346,8 @@ else
   if test \"\$libtool_execute_magic\" != \"$magic\"; then
     file=\"\$0\""
 
-    qECHO=`$ECHO "$ECHO" | $SED "$sed_quote_subst"`
+    func_quote "$ECHO"
+    qECHO=$func_quote_result
     $ECHO "\
 
 # A function that is used when there is no print builtin or printf.
@@ -8596,8 +8597,8 @@ EOF
 	    relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
 	  fi
 	done
-	relink_command="(cd `pwd`; $relink_command)"
-	relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+	func_quote "(cd `pwd`; $relink_command)"
+	relink_command=$func_quote_result
       fi
 
       # Only actually do things if not in dry run mode.
@@ -8843,7 +8844,8 @@ EOF
       done
       # Quote the link command for shipping.
       relink_command="(cd `pwd`; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
-      relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+      func_quote "$relink_command"
+      relink_command=$func_quote_result
       if test yes = "$hardcode_automatic"; then
 	relink_command=
       fi
diff --git a/gl/build-aux/funclib.sh b/gl/build-aux/funclib.sh
index 39d972e..47d8b95 100644
--- a/build-aux/funclib.sh
+++ b/build-aux/funclib.sh
@@ -1,5 +1,5 @@
 # Set a version string for this script.
-scriptversion=2015-01-20.17; # UTC
+scriptversion=2015-10-04.22; # UTC
 
 # General shell script boiler plate, and helper functions.
 # Written by Gary V. Vaughan, 2004
@@ -1026,6 +1026,57 @@ func_relative_path ()
 }
 
 
+# func_quote ARG
+# --------------
+# Aesthetically quote one ARG, store the result into $func_quote_result.  Note
+# that we keep attention to performance here (so far O(N) complexity as long as
+# func_append is O(1)).
+func_quote ()
+{
+    $debug_cmd
+
+    func_quote_result=$1
+
+    case $func_quote_result in
+      *[\\\`\"\$]*)
+        case $func_quote_result in
+          *[\[\*\?]*)
+            func_quote_result=`$ECHO "$func_quote_result" | $SED "$sed_quote_subst"`
+            return 0
+            ;;
+        esac
+
+        func_quote_old_IFS=$IFS
+        for _G_char in '\' '`' '"' '$'
+        do
+          # STATE($1) PREV($2) SEPARATOR($3)
+          set start "" ""
+          func_quote_result=dummy"$_G_char$func_quote_result$_G_char"dummy
+          IFS=$_G_char
+          for _G_part in $func_quote_result
+          do
+            case $1 in
+            quote)
+              func_append func_quote_result "$3$2"
+              set quote "$_G_part" "\\$_G_char"
+              ;;
+            start)
+              set first "" ""
+              func_quote_result=
+              ;;
+            first)
+              set quote "$_G_part" ""
+              ;;
+            esac
+          done
+          IFS=$func_quote_old_IFS
+        done
+        ;;
+      *) ;;
+    esac
+}
+
+
 # func_quote_for_eval ARG...
 # --------------------------
 # Aesthetically quote ARGs to be evaled later.
@@ -1042,12 +1093,8 @@ func_quote_for_eval ()
     func_quote_for_eval_unquoted_result=
     func_quote_for_eval_result=
     while test 0 -lt $#; do
-      case $1 in
-        *[\\\`\"\$]*)
-	  _G_unquoted_arg=`printf '%s\n' "$1" |$SED "$sed_quote_subst"` ;;
-        *)
-          _G_unquoted_arg=$1 ;;
-      esac
+      func_quote "$1"
+      _G_unquoted_arg=$func_quote_result
       if test -n "$func_quote_for_eval_unquoted_result"; then
 	func_append func_quote_for_eval_unquoted_result " $_G_unquoted_arg"
       else

patch the generated file too to keep help2man from generating man pages
https://bugs.gentoo.org/556512

--- a/build-aux/ltmain.sh
+++ b/build-aux/ltmain.sh
@@ -1,5 +1,5 @@
 # Set a version string for this script.
-scriptversion=2015-01-20.17; # UTC
+scriptversion=2015-10-04.22; # UTC
 
 # General shell script boiler plate, and helper functions.
 # Written by Gary V. Vaughan, 2004
@@ -1026,6 +1026,57 @@ func_relative_path ()
 }
 
 
+# func_quote ARG
+# --------------
+# Aesthetically quote one ARG, store the result into $func_quote_result.  Note
+# that we keep attention to performance here (so far O(N) complexity as long as
+# func_append is O(1)).
+func_quote ()
+{
+    $debug_cmd
+
+    func_quote_result=$1
+
+    case $func_quote_result in
+      *[\\\`\"\$]*)
+        case $func_quote_result in
+          *[\[\*\?]*)
+            func_quote_result=`$ECHO "$func_quote_result" | $SED "$sed_quote_subst"`
+            return 0
+            ;;
+        esac
+
+        func_quote_old_IFS=$IFS
+        for _G_char in '\' '`' '"' '$'
+        do
+          # STATE($1) PREV($2) SEPARATOR($3)
+          set start "" ""
+          func_quote_result=dummy"$_G_char$func_quote_result$_G_char"dummy
+          IFS=$_G_char
+          for _G_part in $func_quote_result
+          do
+            case $1 in
+            quote)
+              func_append func_quote_result "$3$2"
+              set quote "$_G_part" "\\$_G_char"
+              ;;
+            start)
+              set first "" ""
+              func_quote_result=
+              ;;
+            first)
+              set quote "$_G_part" ""
+              ;;
+            esac
+          done
+          IFS=$func_quote_old_IFS
+        done
+        ;;
+      *) ;;
+    esac
+}
+
+
 # func_quote_for_eval ARG...
 # --------------------------
 # Aesthetically quote ARGs to be evaled later.
@@ -1042,12 +1093,8 @@ func_quote_for_eval ()
     func_quote_for_eval_unquoted_result=
     func_quote_for_eval_result=
     while test 0 -lt $#; do
-      case $1 in
-        *[\\\`\"\$]*)
-	  _G_unquoted_arg=`printf '%s\n' "$1" |$SED "$sed_quote_subst"` ;;
-        *)
-          _G_unquoted_arg=$1 ;;
-      esac
+      func_quote "$1"
+      _G_unquoted_arg=$func_quote_result
       if test -n "$func_quote_for_eval_unquoted_result"; then
 	func_append func_quote_for_eval_unquoted_result " $_G_unquoted_arg"
       else
@@ -3346,7 +3346,8 @@ else
   if test \"\$libtool_execute_magic\" != \"$magic\"; then
     file=\"\$0\""
 
-    qECHO=`$ECHO "$ECHO" | $SED "$sed_quote_subst"`
+    func_quote "$ECHO"
+    qECHO=$func_quote_result
     $ECHO "\
 
 # A function that is used when there is no print builtin or printf.
@@ -8596,8 +8597,8 @@ EOF
 	    relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
 	  fi
 	done
-	relink_command="(cd `pwd`; $relink_command)"
-	relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+	func_quote "(cd `pwd`; $relink_command)"
+	relink_command=$func_quote_result
       fi
 
       # Only actually do things if not in dry run mode.
@@ -8843,7 +8844,8 @@ EOF
       done
       # Quote the link command for shipping.
       relink_command="(cd `pwd`; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
-      relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+      func_quote "$relink_command"
+      relink_command=$func_quote_result
       if test yes = "$hardcode_automatic"; then
 	relink_command=
       fi
-- 
2.6.2