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
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
dnl This Source Code Form is subject to the terms of the Mozilla Public
dnl License, v. 2.0. If a copy of the MPL was not distributed with this
dnl file, You can obtain one at http://mozilla.org/MPL/2.0/.
dnl Add compiler specific options
dnl ============================================================================
dnl C++ rtti
dnl We don't use it in the code, but it can be usefull for debugging, so give
dnl the user the option of enabling it.
dnl ============================================================================
AC_DEFUN([MOZ_RTTI],
[
if test -z "$_MOZ_USE_RTTI"; then
if test "$GNU_CC"; then
CXXFLAGS="$CXXFLAGS -fno-rtti"
else
case "$target" in
*-mingw*)
CXXFLAGS="$CXXFLAGS -GR-"
esac
fi
fi
])
dnl ========================================================
dnl =
dnl = Debugging Options
dnl =
dnl ========================================================
AC_DEFUN([MOZ_DEBUGGING_OPTS],
[
if test -z "$MOZ_DEBUG" -o -n "$MOZ_ASAN"; then
MOZ_NO_DEBUG_RTL=1
fi
AC_SUBST(MOZ_NO_DEBUG_RTL)
if test -n "$MOZ_DEBUG"; then
if test -n "$COMPILE_ENVIRONMENT"; then
AC_MSG_CHECKING([for valid debug flags])
_SAVE_CFLAGS=$CFLAGS
CFLAGS="$CFLAGS $MOZ_DEBUG_FLAGS"
AC_TRY_COMPILE([#include <stdio.h>],
[printf("Hello World\n");],
_results=yes,
_results=no)
AC_MSG_RESULT([$_results])
if test "$_results" = "no"; then
AC_MSG_ERROR([These compiler flags are invalid: $MOZ_DEBUG_FLAGS])
fi
CFLAGS=$_SAVE_CFLAGS
fi
fi
])
dnl A high level macro for selecting compiler options.
AC_DEFUN([MOZ_COMPILER_OPTS],
[
MOZ_DEBUGGING_OPTS
MOZ_RTTI
if test "$GNU_CC"; then
if test -z "$DEVELOPER_OPTIONS"; then
CFLAGS="$CFLAGS -ffunction-sections -fdata-sections"
CXXFLAGS="$CXXFLAGS -ffunction-sections -fdata-sections"
fi
CFLAGS="$CFLAGS -fno-math-errno"
CXXFLAGS="$CXXFLAGS -fno-exceptions -fno-math-errno"
fi
dnl ========================================================
dnl = Identical Code Folding
dnl ========================================================
if test "$GNU_CC" -a "$GCC_USE_GNU_LD" -a -z "$MOZ_DISABLE_ICF" -a -z "$DEVELOPER_OPTIONS"; then
AC_CACHE_CHECK([whether the linker supports Identical Code Folding],
moz_cv_opt_ld_supports_icf,
[echo 'int foo() {return 42;}' \
'int bar() {return 42;}' \
'int main() {return foo() - bar();}' > conftest.${ac_ext}
# If the linker supports ICF, foo and bar symbols will have
# the same address
if AC_TRY_COMMAND([${CC-cc} -o conftest${ac_exeext} $LDFLAGS -Wl,--icf=safe -ffunction-sections conftest.${ac_ext} $LIBS 1>&2]) &&
test -s conftest${ac_exeext} &&
$LLVM_OBJDUMP -t conftest${ac_exeext} | awk changequote(<<, >>)'{a[<<$>>6] = <<$>>1} END {if (a["foo"] && (a["foo"] != a["bar"])) { exit 1 }}'changequote([, ]); then
moz_cv_opt_ld_supports_icf=yes
else
moz_cv_opt_ld_supports_icf=no
fi
rm -rf conftest*])
if test "$moz_cv_opt_ld_supports_icf" = yes; then
_SAVE_LDFLAGS="$LDFLAGS -Wl,--icf=safe"
LDFLAGS="$LDFLAGS -Wl,--icf=safe -Wl,--print-icf-sections"
AC_TRY_LINK([], [],
[LD_PRINT_ICF_SECTIONS=-Wl,--print-icf-sections],
[LD_PRINT_ICF_SECTIONS=])
AC_SUBST([LD_PRINT_ICF_SECTIONS])
LDFLAGS="$_SAVE_LDFLAGS"
fi
fi
dnl ========================================================
dnl = Detect static linkage of libstdc++
dnl ========================================================
if test "$OS_TARGET" = Linux; then
AC_CACHE_CHECK([whether we're trying to statically link with libstdc++],
moz_cv_opt_static_libstdcxx,
[moz_cv_opt_static_libstdcxx=no
AC_LANG_SAVE
AC_LANG_CPLUSPLUS
cat > conftest.$ac_ext <<EOF
#include <iostream>
int main() { std::cout << 1; }
EOF
dnl This test is quite conservative: it assumes dynamic linkage if the compilation step fails or if
dnl the binary format is not supported. But it still detects basic issues.
if AC_TRY_EVAL([ac_link]) && test -s conftest${ac_exeext} && $LLVM_OBJDUMP --private-headers conftest${ac_exeext} 2> conftest.err 1> conftest.out
then
if test -s conftest.err
then :
elif grep -q -E 'NEEDED.*lib(std)?c\+\+' conftest.out
then :
else moz_cv_opt_static_libstdcxx=yes
fi
fi
AC_LANG_RESTORE
rm -f conftest*
])
if test "$moz_cv_opt_static_libstdcxx" = "yes"; then
AC_MSG_ERROR([Firefox does not support linking statically with libstdc++])
fi
fi
dnl ========================================================
dnl = Automatically remove dead symbols
dnl ========================================================
SANCOV=
if test -n "$LIBFUZZER"; then
case "$LIBFUZZER_FLAGS" in
*-fsanitize-coverage*|*-fsanitize=fuzzer*)
SANCOV=1
;;
esac
fi
if test "$GNU_CC" -a "$GCC_USE_GNU_LD" -a -z "$DEVELOPER_OPTIONS" -a -z "$MOZ_PROFILE_GENERATE" -a -z "$SANCOV"; then
if test -n "$MOZ_DEBUG_FLAGS"; then
dnl See bug 670659
AC_CACHE_CHECK([whether removing dead symbols breaks debugging],
moz_cv_opt_gc_sections_breaks_debug_ranges,
[echo 'int foo() {return 42;}' \
'int bar() {return 1;}' \
'int main() {return foo();}' > conftest.${ac_ext}
if AC_TRY_COMMAND([${CC-cc} -o conftest.${ac_objext} $CFLAGS $MOZ_DEBUG_FLAGS -c conftest.${ac_ext} 1>&2]) &&
AC_TRY_COMMAND([${CC-cc} -o conftest${ac_exeext} $LDFLAGS $MOZ_DEBUG_FLAGS -Wl,--gc-sections conftest.${ac_objext} $LIBS 1>&2]) &&
test -s conftest${ac_exeext} -a -s conftest.${ac_objext}; then
if test "`$PYTHON3 -m mozbuild.configure.check_debug_ranges conftest.${ac_objext} conftest.${ac_ext}`" = \
"`$PYTHON3 -m mozbuild.configure.check_debug_ranges conftest${ac_exeext} conftest.${ac_ext}`"; then
moz_cv_opt_gc_sections_breaks_debug_ranges=no
else
moz_cv_opt_gc_sections_breaks_debug_ranges=yes
fi
else
dnl We really don't expect to get here, but just in case
moz_cv_opt_gc_sections_breaks_debug_ranges="no, but it's broken in some other way"
fi
rm -rf conftest*])
if test "$moz_cv_opt_gc_sections_breaks_debug_ranges" = no; then
DSO_LDOPTS="$DSO_LDOPTS -Wl,--gc-sections"
fi
else
DSO_LDOPTS="$DSO_LDOPTS -Wl,--gc-sections"
fi
fi
if test "$GNU_CC$CLANG_CC"; then
case "${OS_TARGET}" in
Darwin|WASI)
# It's the default on those targets, and clang complains about -pie
# being unused if passed.
;;
*)
MOZ_PROGRAM_LDFLAGS="$MOZ_PROGRAM_LDFLAGS -pie"
;;
esac
fi
AC_SUBST(MOZ_PROGRAM_LDFLAGS)
])
|
