1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
dnl generally useful C++ checks
AC_LANG([C++])
dnl save pre-set values (if any) for variables that are
dnl created by autoconf
PRESET_CXXFLAGS="$CXXFLAGS"
PRESET_LDFLAGS="$LDFLAGS"
dnl check for programs
AC_PROG_CXX
# change default extention for source files
ac_ext=cc
dnl check for optional features
AC_SUBST(std_include)
AC_ARG_ENABLE(std-include,
[ --enable-std-include=DIR Where to find standard C++ headers ],
[
std_include=`echo -I$enableval | sed 's/:/ -I/g'`
CPPFLAGS="$CPPFLAGS $std_include"
],
[ std_include='' ]
)
dnl check if alleged C++ compiler understands C++
AC_MSG_CHECKING(whether the C++ compiler ($CXX) is a C++ compiler)
AC_TRY_COMPILE([
#define Concat(a,b) a ## b
struct T {
virtual ~T();
virtual int m() const = 0;
mutable bool a;
};
template <class P>
struct C: public P {
C(int): c(0) {}
int m() const;
int c;
};
template <class P>
int C<P>::m() const { Concat(re,turn) c; }
inline int test_inline() { return 0; }
],[
// this is main()'s body
static C<T> ct(1);
return 0;
],[
AC_MSG_RESULT(yes)
],[
AC_MSG_RESULT(no)
AC_MSG_ERROR(the compiler ($CXX) failed to pass a simple C++ test; check config.log for details)
])
dnl adjust program options
OLD_CXXFLAGS=$CXXFLAGS
if test -z "$PRESET_CXXFLAGS"
then
if test "x$GXX" = xyes
then [
# reset to preferred options
# replace -O? with -O3
CXXFLAGS=`echo $CXXFLAGS | sed 's/-O[0-9]*/-O3/'`;
# enable useful warnings
CXXFLAGS="$CXXFLAGS -Wall -Wwrite-strings -Woverloaded-virtual"
# avoid disk I/O
CXXFLAGS="$CXXFLAGS -pipe"
# custom host-dependent tuning
case "$host" in
alpha-dec-osf4.*)
# we get random coredumps with g++ -O
echo deleting -On on $host
CXXFLAGS=`echo $CXXFLAGS | sed -e 's/-O[0-9]* *//'`
;;
*-linux-*)
# -O2,3 seems to produce coredumps on RH and MDK linux
echo enforcing -O1 on $host
CXXFLAGS=`echo $CXXFLAGS | sed -e 's/-O[0-9]* */-O1 /'`
;;
esac
] fi
fi
if test "x$PRESET_CXXFLAGS" != "x$CXXFLAGS"
then
AC_MSG_CHECKING(whether custom $CXX flags work)
AC_TRY_COMPILE(
[
],[
return 0;
],[
AC_MSG_RESULT(probably)
echo "changing $CXX flags to $CXXFLAGS"
],[
AC_MSG_RESULT(no)
CXXFLAGS=$OLD_CXXFLAGS
echo "leaving $CXX flags at $CXXFLAGS"
]
)
fi
|
