[PATCH 1/2] libtool: Support quoted arguments in user-supplied flags

* m4/libtool.m4 (_LT_COMPILER_OPTION): Evaluate `lt_compile' variable
  twice in order to unquote user-supplied variables in same manner as
  it made during compilation in Makefiles
  (_LT_COMPILER_C_O): Same
* Makefile.am (TESTSUITE_AT): Add new test
* tests/escaped_cflags.at: New test for quoted CFLAGS. This test would
  work only with autoconf > 2.69; for older autoconf ./configure will
  fail and test will be skipped.
---
 Makefile.am             |  1 +
 m4/libtool.m4           |  4 ++++
 tests/escaped_cflags.at | 44 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 49 insertions(+)
 create mode 100644 tests/escaped_cflags.at

diff --git a/Makefile.am b/Makefile.am
index 6b546092..e99949b2 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -658,6 +658,7 @@ TESTSUITE_AT	= tests/testsuite.at \
 		  tests/libtoolize.at \
 		  tests/libtool.at \
 		  tests/demo.at \
+		  tests/escaped_cflags.at \
 		  tests/pic_flag.at \
 		  tests/with-pic.at \
 		  tests/cdemo.at \
diff --git a/m4/libtool.m4 b/m4/libtool.m4
index f2d1f398..fa7887e0 100644
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -1606,6 +1606,8 @@ AC_CACHE_CHECK([$1], [$2],
    -e 's: [[^ ]]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
    (eval echo "\"\$as_me:$LINENO: $lt_compile\"" >&AS_MESSAGE_LOG_FD)
+   # Evaluate compilation command twice in order to unqoute *FLAGS
+   eval lt_compile="\"$lt_compile\""
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&AS_MESSAGE_LOG_FD
@@ -2088,6 +2090,8 @@ AC_CACHE_CHECK([if $compiler supports -c -o file.$ac_objext],
    -e 's: [[^ ]]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
    (eval echo "\"\$as_me:$LINENO: $lt_compile\"" >&AS_MESSAGE_LOG_FD)
+   # Evaluate compilation command twice in order to unqoute *FLAGS
+   eval lt_compile="\"$lt_compile\""
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&AS_MESSAGE_LOG_FD
diff --git a/tests/escaped_cflags.at b/tests/escaped_cflags.at
new file mode 100644
index 00000000..3dd95ba4
--- /dev/null
+++ b/tests/escaped_cflags.at
@@ -0,0 +1,44 @@
+# escaped_cflags.at -- escaped CFLAGS and tests for PIC flags   -*- Autotest -*-
+
+#   Copyright (C) 2019 Free Software Foundation, Inc.
+#
+#   This file is part of GNU Libtool.
+#
+# GNU Libtool is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# GNU Libtool is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Libtool; see the file COPYING.  If not, a copy
+# can be downloaded from  http://www.gnu.org/licenses/gpl.html,
+# or obtained by writing to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+####
+
+AT_SETUP([check pic_flags with escaped CFLAGS])
+
+AT_DATA([foo.c],
+[[int data = 42;
+int func(void) { return data; }
+]])
+
+# Set up a tests/demo.at style project.
+_LT_DEMO_SETUP
+
+# Bootstrap, and configure it so that we can extract libtool --config
+# settings.
+LT_AT_BOOTSTRAP([], [-I m4], [], [--add-missing], [],
+    [CFLAGS='"-Wall"'], [ignore])
+
+: ${MAKE=make}
+AT_CHECK([$MAKE], [], [stdout], [ignore])
+AT_CHECK([if ./libtool --features | $GREP 'enable shared libraries'; then ]dnl
+	 [  $GREP -i ' -fPIC' stdout; else exit 77; fi], [], [ignore], [ignore])
+
+AT_CLEANUP
-- 
2.21.0