X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/df1ca1b0de2d99879f7b41e64d8bf285f163b1aa..f122444873a1ec499d25ffec5765dcc48dc7b928:/configure.ac

diff --git a/configure.ac b/configure.ac
index f10dabc1..df5670cd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -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]])
@@ -91,7 +91,7 @@ if test "$enable_gcc_warnings" = yes; then
   # -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 -fno-color-diagnostics'
+  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
@@ -143,9 +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])
-  # Variants break strict aliasing analysis.
-  gl_WARN_ADD([-fno-strict-aliasing], [NO_STRICT_ALIAS_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