1 # warnings.m4 serial 11 2 dnl Copyright (C) 2008-2013 Free Software Foundation, Inc. 3 dnl This file is free software; the Free Software Foundation 4 dnl gives unlimited permission to copy and/or distribute it, 5 dnl with or without modifications, as long as this notice is preserved. 6 7 dnl From Simon Josefsson 8 9 # gl_AS_VAR_APPEND(VAR, VALUE) 10 # ---------------------------- 11 # Provide the functionality of AS_VAR_APPEND if Autoconf does not have it. 12 m4_ifdef([AS_VAR_APPEND], 13 [m4_copy([AS_VAR_APPEND], [gl_AS_VAR_APPEND])], 14 [m4_define([gl_AS_VAR_APPEND], 15 [AS_VAR_SET([$1], [AS_VAR_GET([$1])$2])])]) 16 17 18 # gl_COMPILER_OPTION_IF(OPTION, [IF-SUPPORTED], [IF-NOT-SUPPORTED], 19 # [PROGRAM = AC_LANG_PROGRAM()]) 20 # ----------------------------------------------------------------- 21 # Check if the compiler supports OPTION when compiling PROGRAM. 22 # 23 # FIXME: gl_Warn must be used unquoted until we can assume Autoconf 24 # 2.64 or newer. 25 AC_DEFUN([gl_COMPILER_OPTION_IF], 26 [AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_[]_AC_LANG_ABBREV[]_$1])dnl 27 AS_VAR_PUSHDEF([gl_Flags], [_AC_LANG_PREFIX[]FLAGS])dnl 28 AS_LITERAL_IF([$1], 29 [m4_pushdef([gl_Positive], m4_bpatsubst([$1], [^-Wno-], [-W]))], 30 [gl_positive="$1" 31 case $gl_positive in 32 -Wno-*) gl_positive=-W`expr "X$gl_positive" : 'X-Wno-\(.*\)'` ;; 33 esac 34 m4_pushdef([gl_Positive], [$gl_positive])])dnl 35 AC_CACHE_CHECK([whether _AC_LANG compiler handles $1], m4_defn([gl_Warn]), [ 36 gl_save_compiler_FLAGS="$gl_Flags" 37 gl_AS_VAR_APPEND(m4_defn([gl_Flags]), 38 [" $gl_unknown_warnings_are_errors ]m4_defn([gl_Positive])["]) 39 AC_LINK_IFELSE([m4_default([$4], [AC_LANG_PROGRAM([])])], 40 [AS_VAR_SET(gl_Warn, [yes])], 41 [AS_VAR_SET(gl_Warn, [no])]) 42 gl_Flags="$gl_save_compiler_FLAGS" 43 ]) 44 AS_VAR_IF(gl_Warn, [yes], [$2], [$3]) 45 m4_popdef([gl_Positive])dnl 46 AS_VAR_POPDEF([gl_Flags])dnl 47 AS_VAR_POPDEF([gl_Warn])dnl 48 ]) 49 50 # gl_UNKNOWN_WARNINGS_ARE_ERRORS 51 # ------------------------------ 52 # Clang doesn't complain about unknown warning options unless one also 53 # specifies -Wunknown-warning-option -Werror. Detect this. 54 AC_DEFUN([gl_UNKNOWN_WARNINGS_ARE_ERRORS], 55 [gl_COMPILER_OPTION_IF([-Werror -Wunknown-warning-option], 56 [gl_unknown_warnings_are_errors='-Wunknown-warning-option -Werror'], 57 [gl_unknown_warnings_are_errors=])]) 58 59 # gl_WARN_ADD(OPTION, [VARIABLE = WARN_CFLAGS], 60 # [PROGRAM = AC_LANG_PROGRAM()]) 61 # --------------------------------------------- 62 # Adds parameter to WARN_CFLAGS if the compiler supports it when 63 # compiling PROGRAM. For example, gl_WARN_ADD([-Wparentheses]). 64 # 65 # If VARIABLE is a variable name, AC_SUBST it. 66 AC_DEFUN([gl_WARN_ADD], 67 [AC_REQUIRE([gl_UNKNOWN_WARNINGS_ARE_ERRORS]) 68 gl_COMPILER_OPTION_IF([$1], 69 [gl_AS_VAR_APPEND(m4_if([$2], [], [[WARN_CFLAGS]], [[$2]]), [" $1"])], 70 [], 71 [$3]) 72 m4_ifval([$2], 73 [AS_LITERAL_IF([$2], [AC_SUBST([$2])])], 74 [AC_SUBST([WARN_CFLAGS])])dnl 75 ]) 76 77 # Local Variables: 78 # mode: autoconf 79 # End: 80
