[PATCH 7/8] tests: fix failures with G++ 4.8 in Flex scanner

[Akim Demaille]

* configure.ac (WARN_NO_NULL_CONVERSION_CXXFLAGS): Rename as...
(FLEX_SCANNER_CXXFLAGS): this.
Pass -Wno-zero-as-null-pointer-constant to G++ if it supports it.
* examples/calc++/local.mk: Adjust.
---
 configure.ac             |  4 +++-
 examples/calc++/local.mk | 31 +++++++++++++++----------------
 2 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/configure.ac b/configure.ac
index 8f96e54..e6ef8ba 100644
--- a/configure.ac
+++ b/configure.ac
@@ -143,7 +143,9 @@ if test "$enable_gcc_warnings" = yes; then
     gl_WARN_ADD([$i], [WARN_CXXFLAGS_TEST])
   done
   # Clang++ 3.2+ reject C code generated by Flex.
-  gl_WARN_ADD([-Wno-null-conversion], [WARN_NO_NULL_CONVERSION_CXXFLAGS])
+  gl_WARN_ADD([-Wno-null-conversion], [FLEX_SCANNER_CXXFLAGS])
+  # So does G++ 4.8 in std=c++11 mode.
+  gl_WARN_ADD([-Wno-zero-as-null-pointer-constant], [FLEX_SCANNER_CXXFLAGS])
   CXXFLAGS=$save_CXXFLAGS
   AC_LANG_POP([C++])
 fi
diff --git a/examples/calc++/local.mk b/examples/calc++/local.mk
index 6eb31f8..b260001 100644
--- a/examples/calc++/local.mk
+++ b/examples/calc++/local.mk
@@ -44,32 +44,31 @@ CLEANFILES +=                                   \
 # Avoid using BUILT_SOURCES which is too global.
 $(examples_calc___calc___OBJECTS): $(calc_sources_generated)
 
-calc_sources_extracted =                       \
-  examples/calc++/calc++-driver.cc             \
-  examples/calc++/calc++-driver.hh             \
-  examples/calc++/calc++-scanner.ll            \
+calc_sources_extracted =                        \
+  examples/calc++/calc++-driver.cc              \
+  examples/calc++/calc++-driver.hh              \
+  examples/calc++/calc++-scanner.ll             \
   examples/calc++/calc++.cc
-calc_extracted =                               \
-  $(calc_sources_extracted)                    \
+calc_extracted =                                \
+  $(calc_sources_extracted)                     \
   examples/calc++/calc++-parser.yy
 extracted += $(calc_extracted)
-calc_sources_generated =                       \
-  examples/calc++/calc++-parser.cc             \
-  examples/calc++/calc++-parser.hh             \
-  examples/calc++/location.hh                  \
-  examples/calc++/position.hh                  \
+calc_sources_generated =                        \
+  examples/calc++/calc++-parser.cc              \
+  examples/calc++/calc++-parser.hh              \
+  examples/calc++/location.hh                   \
+  examples/calc++/position.hh                   \
   examples/calc++/stack.hh
-calc_sources =                                 \
-  $(calc_sources_extracted)                    \
+calc_sources =                                  \
+  $(calc_sources_extracted)                     \
   $(calc_sources_generated)
 
 if BISON_CXX_WORKS
 check_PROGRAMS += examples/calc++/calc++
-nodist_examples_calc___calc___SOURCES =                \
+nodist_examples_calc___calc___SOURCES =         \
   $(calc_sources)
 
 examples_calc___calc___CPPFLAGS = -I$(top_builddir)/examples/calc++
-examples_calc___calc___CXXFLAGS =                      \
-  $(AM_CXXFLAGS) $(WARN_NO_NULL_CONVERSION_CXXFLAGS)
+examples_calc___calc___CXXFLAGS = $(AM_CXXFLAGS) $(FLEX_SCANNER_CXXFLAGS)
 dist_TESTS += examples/calc++/calc++.test
 endif
-- 
1.8.1.3