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Diffstat (limited to 'm4/gl_warnings.m4')
| -rw-r--r-- | m4/gl_warnings.m4 | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/m4/gl_warnings.m4 b/m4/gl_warnings.m4 new file mode 100644 index 0000000..870472b --- /dev/null +++ b/m4/gl_warnings.m4 @@ -0,0 +1,106 @@ +# warnings.m4 serial 13 +dnl Copyright (C) 2008-2017 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +dnl From Simon Josefsson + +# gl_AS_VAR_APPEND(VAR, VALUE) +# ---------------------------- +# Provide the functionality of AS_VAR_APPEND if Autoconf does not have it. +m4_ifdef([AS_VAR_APPEND], +[m4_copy([AS_VAR_APPEND], [gl_AS_VAR_APPEND])], +[m4_define([gl_AS_VAR_APPEND], +[AS_VAR_SET([$1], [AS_VAR_GET([$1])$2])])]) + + +# gl_COMPILER_OPTION_IF(OPTION, [IF-SUPPORTED], [IF-NOT-SUPPORTED], +# [PROGRAM = AC_LANG_PROGRAM()]) +# ----------------------------------------------------------------- +# Check if the compiler supports OPTION when compiling PROGRAM. +# +# The effects of this macro depend on the current language (_AC_LANG). +AC_DEFUN([gl_COMPILER_OPTION_IF], +[ +dnl FIXME: gl_Warn must be used unquoted until we can assume Autoconf +dnl 2.64 or newer. +AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_[]_AC_LANG_ABBREV[]_$1])dnl +AS_VAR_PUSHDEF([gl_Flags], [_AC_LANG_PREFIX[]FLAGS])dnl +AS_LITERAL_IF([$1], + [m4_pushdef([gl_Positive], m4_bpatsubst([$1], [^-Wno-], [-W]))], + [gl_positive="$1" +case $gl_positive in + -Wno-*) gl_positive=-W`expr "X$gl_positive" : 'X-Wno-\(.*\)'` ;; +esac +m4_pushdef([gl_Positive], [$gl_positive])])dnl +AC_CACHE_CHECK([whether _AC_LANG compiler handles $1], m4_defn([gl_Warn]), [ + gl_save_compiler_FLAGS="$gl_Flags" + gl_AS_VAR_APPEND(m4_defn([gl_Flags]), + [" $gl_unknown_warnings_are_errors ]m4_defn([gl_Positive])["]) + AC_LINK_IFELSE([m4_default([$4], [AC_LANG_PROGRAM([])])], + [AS_VAR_SET(gl_Warn, [yes])], + [AS_VAR_SET(gl_Warn, [no])]) + gl_Flags="$gl_save_compiler_FLAGS" +]) +AS_VAR_IF(gl_Warn, [yes], [$2], [$3]) +m4_popdef([gl_Positive])dnl +AS_VAR_POPDEF([gl_Flags])dnl +AS_VAR_POPDEF([gl_Warn])dnl +]) + +# gl_UNKNOWN_WARNINGS_ARE_ERRORS +# ------------------------------ +# Clang doesn't complain about unknown warning options unless one also +# specifies -Wunknown-warning-option -Werror. Detect this. +# +# The effects of this macro depend on the current language (_AC_LANG). +AC_DEFUN([gl_UNKNOWN_WARNINGS_ARE_ERRORS], +[_AC_LANG_DISPATCH([$0], _AC_LANG, $@)]) + +# Specialization for _AC_LANG = C. This macro can be AC_REQUIREd. +# Use of m4_defun rather than AC_DEFUN works around a bug in autoconf < 2.63b. +m4_defun([gl_UNKNOWN_WARNINGS_ARE_ERRORS(C)], +[ + AC_LANG_PUSH([C]) + gl_UNKNOWN_WARNINGS_ARE_ERRORS_IMPL + AC_LANG_POP([C]) +]) + +# Specialization for _AC_LANG = C++. This macro can be AC_REQUIREd. +# Use of m4_defun rather than AC_DEFUN works around a bug in autoconf < 2.63b. +m4_defun([gl_UNKNOWN_WARNINGS_ARE_ERRORS(C++)], +[ + AC_LANG_PUSH([C++]) + gl_UNKNOWN_WARNINGS_ARE_ERRORS_IMPL + AC_LANG_POP([C++]) +]) + +AC_DEFUN([gl_UNKNOWN_WARNINGS_ARE_ERRORS_IMPL], +[gl_COMPILER_OPTION_IF([-Werror -Wunknown-warning-option], + [gl_unknown_warnings_are_errors='-Wunknown-warning-option -Werror'], + [gl_unknown_warnings_are_errors=])]) + +# gl_WARN_ADD(OPTION, [VARIABLE = WARN_CFLAGS/WARN_CXXFLAGS], +# [PROGRAM = AC_LANG_PROGRAM()]) +# ----------------------------------------------------------- +# Adds parameter to WARN_CFLAGS/WARN_CXXFLAGS if the compiler supports it +# when compiling PROGRAM. For example, gl_WARN_ADD([-Wparentheses]). +# +# If VARIABLE is a variable name, AC_SUBST it. +# +# The effects of this macro depend on the current language (_AC_LANG). +AC_DEFUN([gl_WARN_ADD], +[AC_REQUIRE([gl_UNKNOWN_WARNINGS_ARE_ERRORS(]_AC_LANG[)]) +gl_COMPILER_OPTION_IF([$1], + [gl_AS_VAR_APPEND(m4_if([$2], [], [[WARN_]_AC_LANG_PREFIX[FLAGS]], [[$2]]), [" $1"])], + [], + [$3]) +m4_ifval([$2], + [AS_LITERAL_IF([$2], [AC_SUBST([$2])])], + [AC_SUBST([WARN_]_AC_LANG_PREFIX[FLAGS])])dnl +]) + +# Local Variables: +# mode: autoconf +# End: |