Add a check for misbehaving -Wcomment from gcc-4.7 and add

-Wno-comment to the compilation flags if so.

Patch by Filipe Cabecinhas, configure regenerated by me.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221323 91177308-0d34-0410-b5e6-96231b3b80d8

Makefile.config.in

@@ -396,6 +396,8 @@ COVERED_SWITCH_DEFAULT = @COVERED_SWITCH_DEFAULT@
 NO_UNINITIALIZED = @NO_UNINITIALIZED@
 # -Wno-maybe-uninitialized
 NO_MAYBE_UNINITIALIZED = @NO_MAYBE_UNINITIALIZED@
+# -Wno-comment
+NO_COMMENT = @NO_COMMENT@
 
 # Was polly found in tools/polly?
 LLVM_HAS_POLLY = @LLVM_HAS_POLLY@

Makefile.rules

@@ -679,7 +679,7 @@ endif
 CompileCommonOpts += -Wall -W -Wno-unused-parameter -Wwrite-strings \
                      $(EXTRA_OPTIONS) $(COVERED_SWITCH_DEFAULT) \
                      $(NO_UNINITIALIZED) $(NO_MAYBE_UNINITIALIZED) \
-                     $(NO_MISSING_FIELD_INITIALIZERS)
+                     $(NO_MISSING_FIELD_INITIALIZERS) $(NO_COMMENT)
 # Enable cast-qual for C++; the workaround is to use const_cast.
 CXX.Flags += -Wcast-qual
 

autoconf/configure.ac

@@ -1386,7 +1386,27 @@ then
     CXX_FLAG_CHECK(NO_UNINITIALIZED, [-Wno-uninitialized])
   fi
 fi
-AC_MSG_RESULT([$NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS $COVERED_SWITCH_DEFAULT $NO_UNINITIALIZED $NO_MAYBE_UNINITIALIZED])
+
+dnl Check for misbehaving -Wcomment (gcc-4.7 has this) and maybe add
+dnl -Wno-comment to the flags.
+no_comment=
+llvm_cv_old_cxxflags="$CXXFLAGS"
+CXXFLAGS="$CXXFLAGS -Wcomment -Werror"
+AC_COMPILE_IFELSE(
+[
+  AC_LANG_SOURCE([[// Comment \o\
+// Another comment
+int main() { return 0; }
+  ]])
+],
+[
+  no_comment=-Wno-comment
+],
+[])
+AC_SUBST(NO_COMMENT, [$no_comment])
+CXXFLAGS="$llvm_cv_old_cxxflags"
+
+AC_MSG_RESULT([$NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS $COVERED_SWITCH_DEFAULT $NO_UNINITIALIZED $NO_MAYBE_UNINITIALIZED $NO_COMMENT])
 
 AC_ARG_WITH([python],
             [AS_HELP_STRING([--with-python], [path to python])],

configure

@@ -762,6 +762,7 @@ NO_MISSING_FIELD_INITIALIZERS
 COVERED_SWITCH_DEFAULT
 NO_MAYBE_UNINITIALIZED
 NO_UNINITIALIZED
+NO_COMMENT
 PYTHON
 HAVE_DLOPEN
 HAVE_TERMINFO
@@ -8066,8 +8067,74 @@ then
 
   fi
 fi
-{ echo "$as_me:$LINENO: result: $NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS $COVERED_SWITCH_DEFAULT $NO_UNINITIALIZED $NO_MAYBE_UNINITIALIZED" >&5
-echo "${ECHO_T}$NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS $COVERED_SWITCH_DEFAULT $NO_UNINITIALIZED $NO_MAYBE_UNINITIALIZED" >&6; }
+
+no_comment=
+llvm_cv_old_cxxflags="$CXXFLAGS"
+CXXFLAGS="$CXXFLAGS -Wcomment -Werror"
+cat >conftest.$ac_ext <<_ACEOF
+
+  /* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+// Comment \o\
+// Another comment
+int main() { return 0; }
+
+
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+	 { ac_try='test -z "$ac_c_werror_flag" || test ! -s conftest.err'
+  { (case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_try") 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+	 { ac_try='test -s conftest.$ac_objext'
+  { (case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_try") 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+  no_comment=-Wno-comment
+
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+NO_COMMENT=$no_comment
+
+CXXFLAGS="$llvm_cv_old_cxxflags"
+
+{ echo "$as_me:$LINENO: result: $NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS $COVERED_SWITCH_DEFAULT $NO_UNINITIALIZED $NO_MAYBE_UNINITIALIZED $NO_COMMENT" >&5
+echo "${ECHO_T}$NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS $COVERED_SWITCH_DEFAULT $NO_UNINITIALIZED $NO_MAYBE_UNINITIALIZED $NO_COMMENT" >&6; }
 
 
 # Check whether --with-python was given.
@@ -19278,6 +19345,7 @@ NO_MISSING_FIELD_INITIALIZERS!$NO_MISSING_FIELD_INITIALIZERS$ac_delim
 COVERED_SWITCH_DEFAULT!$COVERED_SWITCH_DEFAULT$ac_delim
 NO_MAYBE_UNINITIALIZED!$NO_MAYBE_UNINITIALIZED$ac_delim
 NO_UNINITIALIZED!$NO_UNINITIALIZED$ac_delim
+NO_COMMENT!$NO_COMMENT$ac_delim
 PYTHON!$PYTHON$ac_delim
 HAVE_DLOPEN!$HAVE_DLOPEN$ac_delim
 HAVE_TERMINFO!$HAVE_TERMINFO$ac_delim
@@ -19312,7 +19380,7 @@ LIBOBJS!$LIBOBJS$ac_delim
 LTLIBOBJS!$LTLIBOBJS$ac_delim
 _ACEOF
 
-  if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 95; then
+  if test `sed -n "s/.*$ac_delim\$/X/p" conf$$subs.sed | grep -c X` = 96; then
     break
   elif $ac_last_try; then
     { { echo "$as_me:$LINENO: error: could not make $CONFIG_STATUS" >&5
@@ -19331,7 +19399,7 @@ fi
 
 cat >>$CONFIG_STATUS <<_ACEOF
 cat >"\$tmp/subs-2.sed" <<\CEOF$ac_eof
-/@[a-zA-Z_][a-zA-Z_0-9]*@/!b end
+/@[a-zA-Z_][a-zA-Z_0-9]*@/!b
 _ACEOF
 sed '
 s/[,\\&]/\\&/g; s/@/@|#_!!_#|/g
@@ -19344,8 +19412,6 @@ N; s/^.*\n//; s/[,\\&]/\\&/g; s/@/@|#_!!_#|/g; b n
 ' >>$CONFIG_STATUS <conf$$subs.sed
 rm -f conf$$subs.sed
 cat >>$CONFIG_STATUS <<_ACEOF
-:end
-s/|#_!!_#|//g
 CEOF$ac_eof
 _ACEOF
 
@@ -19593,7 +19659,7 @@ s&@abs_builddir@&$ac_abs_builddir&;t t
 s&@abs_top_builddir@&$ac_abs_top_builddir&;t t
 s&@INSTALL@&$ac_INSTALL&;t t
 $ac_datarootdir_hack
-" $ac_file_inputs | sed -f "$tmp/subs-1.sed" | sed -f "$tmp/subs-2.sed" >$tmp/out
+" $ac_file_inputs | sed -f "$tmp/subs-1.sed" | sed -f "$tmp/subs-2.sed" | sed 's/|#_!!_#|//g' >$tmp/out
 
 test -z "$ac_datarootdir_hack$ac_datarootdir_seen" &&
   { ac_out=`sed -n '/\${datarootdir}/p' "$tmp/out"`; test -n "$ac_out"; } &&