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
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
|
Patch-Source: https://github.com/zephyrproject-rtos/gcc/pull/8
From 55addb0c0c5ff5e0aab85574aa26abf175af85c8 Mon Sep 17 00:00:00 2001
From: Stephanos Ioannidis <root@stephanos.io>
Date: Mon, 25 Jul 2022 23:10:41 +0900
Subject: [PATCH] libstdc++: Do not check getentropy and arc4random for cross builds
The "getentropy" and "arc4random" check may not yield a correct result
for the cross compile builds because linking is often not available for
them and the C library headers (notoriously, newlib) may still declare
these function prototypes even if they are not actually part of the
final library -- for this reason, this commit disables the "getentropy"
and "arc4random" checks for non-native builds.
This effectively prevents the std::random_device from making use of
these functions when `--with-newlib` is specified, which is indeed a
correct behaviour because the newlib does not provide a default stub
for the "getentropy" function (also note that the newlib "arc4random"
implementation internally calls the missing "getentropy" function).
For other C libraries, the `GLIBCXX_CROSSCONFIG` function may hard-code
the availability of these functions by manually defining
`HAVE_GETENTROPY` and `HAVE_ARC4RANDOM`, or by calling the
`GLIBCXX_CHECK_GETENTROPY` and `GLIBCXX_CHECK_ARC4RANDOM` functions.
libstdc++-v3:
* configure.ac: Relocate GLIBCXX_CHECK_GETENTROPY and
GLIBCXX_CHECK_ARC4RANDOM
* configure: Regenerate.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
---
libstdc++-v3/configure | 300 +++++++++++++++++++-------------------
libstdc++-v3/configure.ac | 8 +-
2 files changed, 154 insertions(+), 154 deletions(-)
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 0ce74e8202443..5d43b56b03ffa 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -28088,6 +28088,156 @@ $as_echo "#define _GLIBCXX_USE_RANDOM_TR1 1" >>confdefs.h
+ # Check for other random number APIs
+
+
+
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for getentropy" >&5
+$as_echo_n "checking for getentropy... " >&6; }
+if ${glibcxx_cv_getentropy+:} false; then :
+ $as_echo_n "(cached) " >&6
+else
+
+ if test x$gcc_no_link = xyes; then
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+#include <unistd.h>
+int
+main ()
+{
+unsigned i;
+ ::getentropy(&i, sizeof(i));
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+ glibcxx_cv_getentropy=yes
+else
+ glibcxx_cv_getentropy=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+else
+ if test x$gcc_no_link = xyes; then
+ as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
+fi
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+#include <unistd.h>
+int
+main ()
+{
+unsigned i;
+ ::getentropy(&i, sizeof(i));
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_link "$LINENO"; then :
+ glibcxx_cv_getentropy=yes
+else
+ glibcxx_cv_getentropy=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+ conftest$ac_exeext conftest.$ac_ext
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_getentropy" >&5
+$as_echo "$glibcxx_cv_getentropy" >&6; }
+
+ if test $glibcxx_cv_getentropy = yes; then
+
+$as_echo "#define HAVE_GETENTROPY 1" >>confdefs.h
+
+ fi
+ ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+
+
+
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for arc4random" >&5
+$as_echo_n "checking for arc4random... " >&6; }
+if ${glibcxx_cv_arc4random+:} false; then :
+ $as_echo_n "(cached) " >&6
+else
+
+ if test x$gcc_no_link = xyes; then
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+#include <stdlib.h>
+int
+main ()
+{
+unsigned i = ::arc4random();
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+ glibcxx_cv_arc4random=yes
+else
+ glibcxx_cv_arc4random=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+else
+ if test x$gcc_no_link = xyes; then
+ as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
+fi
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+#include <stdlib.h>
+int
+main ()
+{
+unsigned i = ::arc4random();
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_link "$LINENO"; then :
+ glibcxx_cv_arc4random=yes
+else
+ glibcxx_cv_arc4random=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+ conftest$ac_exeext conftest.$ac_ext
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_arc4random" >&5
+$as_echo "$glibcxx_cv_arc4random" >&6; }
+
+ if test $glibcxx_cv_arc4random = yes; then
+
+$as_echo "#define HAVE_ARC4RANDOM 1" >>confdefs.h
+
+ fi
+ ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+
# For TLS support.
@@ -75519,156 +75669,6 @@ $as_echo "#define _GLIBCXX_X86_RDSEED 1" >>confdefs.h
fi
-# Check for other random number APIs
-
-
-
- ac_ext=cpp
-ac_cpp='$CXXCPP $CPPFLAGS'
-ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
-
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for getentropy" >&5
-$as_echo_n "checking for getentropy... " >&6; }
-if ${glibcxx_cv_getentropy+:} false; then :
- $as_echo_n "(cached) " >&6
-else
-
- if test x$gcc_no_link = xyes; then
- cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h. */
-#include <unistd.h>
-int
-main ()
-{
-unsigned i;
- ::getentropy(&i, sizeof(i));
- ;
- return 0;
-}
-_ACEOF
-if ac_fn_cxx_try_compile "$LINENO"; then :
- glibcxx_cv_getentropy=yes
-else
- glibcxx_cv_getentropy=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-else
- if test x$gcc_no_link = xyes; then
- as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
-fi
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h. */
-#include <unistd.h>
-int
-main ()
-{
-unsigned i;
- ::getentropy(&i, sizeof(i));
- ;
- return 0;
-}
-_ACEOF
-if ac_fn_cxx_try_link "$LINENO"; then :
- glibcxx_cv_getentropy=yes
-else
- glibcxx_cv_getentropy=no
-fi
-rm -f core conftest.err conftest.$ac_objext \
- conftest$ac_exeext conftest.$ac_ext
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_getentropy" >&5
-$as_echo "$glibcxx_cv_getentropy" >&6; }
-
- if test $glibcxx_cv_getentropy = yes; then
-
-$as_echo "#define HAVE_GETENTROPY 1" >>confdefs.h
-
- fi
- ac_ext=c
-ac_cpp='$CPP $CPPFLAGS'
-ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-ac_compiler_gnu=$ac_cv_c_compiler_gnu
-
-
-
-
-
- ac_ext=cpp
-ac_cpp='$CXXCPP $CPPFLAGS'
-ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
-
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking for arc4random" >&5
-$as_echo_n "checking for arc4random... " >&6; }
-if ${glibcxx_cv_arc4random+:} false; then :
- $as_echo_n "(cached) " >&6
-else
-
- if test x$gcc_no_link = xyes; then
- cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h. */
-#include <stdlib.h>
-int
-main ()
-{
-unsigned i = ::arc4random();
- ;
- return 0;
-}
-_ACEOF
-if ac_fn_cxx_try_compile "$LINENO"; then :
- glibcxx_cv_arc4random=yes
-else
- glibcxx_cv_arc4random=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-else
- if test x$gcc_no_link = xyes; then
- as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
-fi
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h. */
-#include <stdlib.h>
-int
-main ()
-{
-unsigned i = ::arc4random();
- ;
- return 0;
-}
-_ACEOF
-if ac_fn_cxx_try_link "$LINENO"; then :
- glibcxx_cv_arc4random=yes
-else
- glibcxx_cv_arc4random=no
-fi
-rm -f core conftest.err conftest.$ac_objext \
- conftest$ac_exeext conftest.$ac_ext
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_arc4random" >&5
-$as_echo "$glibcxx_cv_arc4random" >&6; }
-
- if test $glibcxx_cv_arc4random = yes; then
-
-$as_echo "#define HAVE_ARC4RANDOM 1" >>confdefs.h
-
- fi
- ac_ext=c
-ac_cpp='$CPP $CPPFLAGS'
-ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-ac_compiler_gnu=$ac_cv_c_compiler_gnu
-
-
-
# This depends on GLIBCXX_ENABLE_SYMVERS and GLIBCXX_IS_NATIVE.
# Do checks for resource limit functions.
diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index e59bcdb29441f..05cdfcddbc43b 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -269,6 +269,10 @@ if $GLIBCXX_IS_NATIVE; then
# For /dev/random and /dev/urandom for std::random_device.
GLIBCXX_CHECK_DEV_RANDOM
+ # Check for other random number APIs
+ GLIBCXX_CHECK_GETENTROPY
+ GLIBCXX_CHECK_ARC4RANDOM
+
# For TLS support.
GCC_CHECK_TLS
@@ -474,10 +478,6 @@ GLIBCXX_CHECK_X86_RDRAND
# Check if assembler supports rdseed opcode.
GLIBCXX_CHECK_X86_RDSEED
-# Check for other random number APIs
-GLIBCXX_CHECK_GETENTROPY
-GLIBCXX_CHECK_ARC4RANDOM
-
# This depends on GLIBCXX_ENABLE_SYMVERS and GLIBCXX_IS_NATIVE.
GLIBCXX_CONFIGURE_TESTSUITE
|
