Upstream | cc2ee17 | 1970-01-12 13:46:40 +0000 | [diff] [blame^] | 1 | dnl AX_CXXFLAGS_OPTIONS(var-name, option) |
| 2 | dnl add option to var-name if $CXX support it. |
| 3 | AC_DEFUN([AX_CHECK_PRECOMPILED_HEADER], [ |
| 4 | AC_MSG_CHECKING([whether ${CXX} support precompiled header]) |
| 5 | AC_LANG_SAVE |
| 6 | AC_LANG_CPLUSPLUS |
| 7 | SAVE_CXXFLAGS=$CXXFLAGS |
| 8 | dnl we consider than if -Winvalid-pch is accepted pch will works ... |
| 9 | CXXFLAGS=-Winvalid-pch |
| 10 | dnl but we don't want -Winvalid-pch else compilation will fail due -Werror and |
| 11 | dnl the fact than some pch will be invalid for the given compilation option |
| 12 | AC_TRY_COMPILE(,[;],AC_MSG_RESULT([yes]); $1="${$1} -include bits/stdc++.h", AC_MSG_RESULT([no])) |
| 13 | CXXFLAGS=$SAVE_CXXFLAGS |
| 14 | AC_LANG_RESTORE |
| 15 | ]) |