1 <!-- 2 Copyright 2010 The Android Open Source Project 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 --> 16 17 # Known Issues # 18 19 Even with our best care, small problems sometimes slip in. This page keeps 20 track of the known issues around using the Android source code. 21 22 ## Missing CTS Native XML Generator ## 23 24 **Symptom**: On some builds of IceCreamSandwich and later, the following 25 warning is printed early during the build: 26 `/bin/bash: line 0: cd: cts/tools/cts-native-xml-generator/src/res: No 27 such file or directory` 28 29 **Cause**: Some makefile references that path, which doesn't exist. 30 31 **Fix**: None. This is a harmless warning. 32 33 ## Black Gingerbread Emulator ## 34 35 **Symptom**: The emulator built directly from the gingerbread branch 36 doesn't start and stays stuck on a black screen. 37 38 **Cause**: The gingerbread branch uses version R7 of the emulator, 39 which doesn't have all the features necessary to run recent versions 40 of gingerbread. 41 42 **Fix**: Use version R12 of the emulator, and a newer kernel that matches 43 those tools. No need to do a clean build. 44 45 $ repo forall platform/external/qemu -c git checkout aosp/tools_r12 46 $ make 47 $ emulator -kernel prebuilt/android-arm/kernel/kernel-qemu-armv7 48 49 ## Emulator built on MacOS 10.7 Lion doesn't work. ## 50 51 **Symptom**: The emulator (any version) built on MacOS 10.7 Lion 52 and/or on XCode 4.x doesn't start. 53 54 **Cause**: Some change in the development environment causes 55 the emulator to be compiled in a way that prevents it from working. 56 57 **Fix**: Use an emulator binary from the SDK, which is built on 58 MacOS 10.6 with XCode 3 and works on MacOS 10.7. 59 60 ## Difficulties syncing the source code (proxy issues). ## 61 62 **Symptom**: `repo init` or `repo sync` fail with http errors, 63 typically 403 or 500. 64 65 **Cause**: There are quite a few possible causes, most often 66 related to http proxies, which have difficulties handling the 67 large amounts of data getting transfered. 68 69 **Fix**: While there's no general solution, using python 2.7 70 and explicitly using `repo sync -j1` have been reported to 71 improve the situation for some users. 72 73 ## Difficulties syncing the source tree (VirtualBox Ethernet issues). ## 74 75 **Symptom**: When running `repo sync` in some VirtualBox installations, 76 the process hangs or fails with a variety of possible symptoms. 77 One such symptom is 78 `DownloadError: HTTP 500 (Internal Server Error: Server got itself in trouble)`. 79 80 **Cause**: The default network behavior of VirtualBox is to use 81 NAT (Network Addrss Translation) to connect the guest system to 82 the network. The heavy network activity of repo sync triggers some 83 corner cases in the NAT code. 84 85 **Fix**: Configure VirtualBox to use bridged network instead of NAT. 86 87 ## Difficulties syncing the source tree (DNS issues). ## 88 89 **Symptom**: When running `repo sync`, the process fails with 90 various errors related to not recognizing the hostname. One such 91 error is `<urlopen error [Errno -2] Name or service not known>`. 92 93 **Cause**: Some DNS systems have a hard time coping with the 94 high number of queries involved in syncing the source tree 95 (there can be several hundred requests in a worst-case scenario). 96 97 **Fix**: Manually resolve the relevant hostnames, and hard-code 98 those results locally. 99 100 You can resolve them with the `nslookup` command, which will give 101 you one numerical IP address for each of those (typically in the 102 "Address" part of the output). 103 104 $ nslookup googlesource.com 105 $ nslookup android.googlesource.com 106 107 You can then hard-code them locally by editing `/etc/hosts`, and 108 adding two lines in that file, of the form: 109 110 aaa.bbb.ccc.ddd googlesource.com 111 eee.fff.ggg.hhh android.googlesource.com 112 113 Note that this will only work as long as the servers' addresses 114 don't change, and if they do and you can't connect you'll have 115 to resolve those hostnames again and edit `etc/hosts` accordingly. 116 117 ## Difficulties syncing the source tree (TCP issues). ## 118 119 **Symptom**: `repo sync` hangs while syncing, often when it's 120 completed 99% of the sync. 121 122 **Cause**: Some settings in the TCP/IP stack cause difficulties 123 in some network environments, such that `repo sync` neither completes 124 nor fails. 125 126 **Fix**: On linux, `sysctl -w net.ipv4.tcp_window_scaling=0`. On 127 MacOS, disable the rfc1323 extension in the network settings. 128 129 ## `make snod` and emulator builds. ## 130 131 **Symptom**: When using `make snod` (make system no dependencies) 132 on emulator builds, the resulting build doesn't work. 133 134 **Cause**: All emulator builds now run Dex optimization at build 135 time by default, which requires to follow all dependencies to 136 re-optimize the applications each time the framework changes. 137 138 **Fix**: Locally disable Dex optimizations with 139 `export WITH_DEXPREOPT=false`, delete the existing optimized 140 versions with `make installclean` and run a full build to 141 re-generate non-optimized versions. After that, `make snod` 142 will work. 143 144 ## "Permission Denied" during builds. ## 145 146 **Symptom**: All builds fail with "Permission Denied", possibly 147 along with anti-virus warnings. 148 149 **Cause**: Some anti-virus programs mistakenly recognize some 150 source files in the Android source tree as if they contained 151 viruses. 152 153 **Fix**: After verifying that there are no actual viruses 154 involved, disable anti-virus on the Android tree. This has 155 the added benefit of reducing build times. 156 157 ## Camera, GPS and NFC don't work on Galaxy Nexus. ## 158 159 **Symptom**: Camera, GPS and NFC don't work on Galaxy Nexus. 160 As an example, the Camera application crashes as soon as it's 161 launched. 162 163 **Cause**: Those hardware peripherals require proprietary 164 libraries that aren't available in the Android Open Source 165 Project. 166 167 **Fix**: None. 168 169 ## Build errors related to using the wrong compiler. ## 170 171 **Symptom**: The build fails with various symptoms. One 172 such symptom is `cc1: error: unrecognized command line option "-m32"` 173 174 **Cause**: The Android build system uses the default compiler 175 in the PATH, assuming it's a suitable compiler to generate 176 binaries that run on the host. Other situations (e.g. using 177 the Android NDK or building the kernel) cause the default 178 compiler to not be a host compiler. 179 180 **Fix**: Use a "clean" shell, in which no previous 181 actions could have swapped the default compiler. 182 183 ## Build errors caused by non-default tool settings. ## 184 185 **Symptom**: The build fails with various symptoms, possibly 186 complinaing about missing files or files that have the 187 wrong format. One such symptom is `member [...] in archive is not an object`. 188 189 **Cause**: The Android build system tends to use many host tools 190 and to rely on their default behaviors. Some settings change 191 those tools' behaviors and make them behave in ways that 192 confuse the build system. Variables known to cause such 193 issues are `CDPATH` and `GREP_OPTIONS`. 194 195 **Fix**: Build Android in an environment that has as few 196 customizations as possible. 197
