tests: enable -Wsign-compare and fix corresponding warnings

[bison.git] / configure.ac

diff --git a/configure.ac b/configure.ac
index eb39c617c48b644f4dfc346674f4cc8ce57925df..df5670cd5d7167b4f6762c270e1577550028671f 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 # Configure template for GNU Bison.                   -*-Autoconf-*-
 #
-# Copyright (C) 2001-2012 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -18,7 +18,7 @@
 # In order for some versions of Sun Studio to compile our C++ test cases
 # correctly, we need Autoconf 2.64 or better to handle the restrict
 # keyword in at least string.h from gnulib.  We need Autoconf 2.68 or
-# better to avoid a typo in the `configure --help' entry for the YACC
+# better to avoid a typo in the 'configure --help' entry for the YACC
 # environment variable.
 AC_PREREQ([2.68])
 m4_pattern_forbid([^gl_[A-Z]])
@@ -26,7 +26,7 @@ m4_pattern_forbid([^gl_[A-Z]])
 AC_INIT([GNU Bison],
         m4_esyscmd([build-aux/git-version-gen .tarball-version]),
         [bug-bison@gnu.org])
-AC_SUBST([PACKAGE_COPYRIGHT_YEAR], [2012])
+AC_SUBST([PACKAGE_COPYRIGHT_YEAR], [2013])
 AC_DEFINE_UNQUOTED([PACKAGE_COPYRIGHT_YEAR], [$PACKAGE_COPYRIGHT_YEAR],
                    [The copyright year for this package])
 
@@ -86,6 +86,12 @@ if test "$enable_gcc_warnings" = yes; then
     -Wformat -Wpointer-arith -Wwrite-strings'
   warn_c='-Wbad-function-cast -Wshadow -Wstrict-prototypes'
   warn_cxx='-Wnoexcept'
+  # Warnings for the test suite only.
+  #
+  # -fno-color-diagnostics: Clang's use of colors in the error
+  # messages is confusing the tests looking at the compiler's output
+  # (e.g., synclines.at).
+  warn_tests='-Wundef -pedantic -Wsign-compare -fno-color-diagnostics'
 
   AC_LANG_PUSH([C])
   # Clang supports many of GCC's -W options, but only issues warnings
@@ -114,12 +120,13 @@ if test "$enable_gcc_warnings" = yes; then
     AS_VAR_APPEND([WARN_CFLAGS], [" $WARN_CFLAGS_TEST"])
 
   # Warnings for the test suite only.
-  gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST])
-  gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST])
+  for i in $warn_tests;
+  do
+    gl_WARN_ADD([$i], [WARN_CFLAGS_TEST])
+  done
   CFLAGS=$save_CFLAGS
   AC_LANG_POP([C])
 
-
   AC_LANG_PUSH([C++])
   save_CXXFLAGS=$CXXFLAGS
   gl_WARN_ADD([-Werror=unknown-warning-option], [CXXFLAGS])
@@ -131,10 +138,14 @@ if test "$enable_gcc_warnings" = yes; then
               [AC_LANG_PROGRAM([], [nullptr])])
   gl_WARN_ADD([-Werror], [WERROR_CXXFLAGS])
   # Warnings for the test suite only.
-  gl_WARN_ADD([-Wundef], [WARN_CXXFLAGS_TEST])
-  gl_WARN_ADD([-pedantic], [WARN_CXXFLAGS_TEST])
-  # Variants break strict aliasing analysis.
-  gl_WARN_ADD([-fno-strict-aliasing], [NO_STRICT_ALIAS_CXXFLAGS])
+  for i in $warn_tests;
+  do
+    gl_WARN_ADD([$i], [WARN_CXXFLAGS_TEST])
+  done
+  # Clang++ 3.2+ reject C code generated by Flex.
+  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