在 Cygwin 上使用 RVM 安装 Ruby 时遇到问题

Question

我在 Windows 上，目前拥有 Ruby v2.1.5，因为它是 RailsInstaller 附带的。但是，我需要为另一个项目降级到 2.1.1，但我不知道该怎么做。

我在 Cygwin 上安装了 rvm，但在尝试执行 rvm install 2.1.1 时遇到了这些问题

Searching for binary rubies, this might take some time.
No binary rubies available for: cygwin/unknown/x86_64/ruby-2.1.1.
Continuing with compilation. Please read 'rvm help mount' to get more 
information on binary rubies.

和

Checking requirements for cygwin.
Installing requirements for cygwin.
Updating system.
Installing required packages: mingw64-i686-gcc, mingw64-x86_64-gcc.
Requirements installation successful.
Installing Ruby from source to: /home/K/.rvm/rubies/ruby-2.1.1, this may take a while depending on your cpu(s)...
ruby-2.1.1 - #downloading ruby-2.1.1, this may take a while depending on your connection...
ruby-2.1.1 - #extracting ruby-2.1.1 to /home/K/.rvm/src/ruby-2.1.1....
ruby-2.1.1 - #applying patch /home/K/.rvm/patches/ruby/2.1.1/libyaml.patch.
ruby-2.1.1 - #applying patch /home/K/.rvm/patches/ruby/changeset_r45225.diff.
ruby-2.1.1 - #applying patch /home/K/.rvm/patches/ruby/changeset_r45240.diff.
ruby-2.1.1 - #configuring....................................................
ruby-2.1.1 - #post-configuration..
ruby-2.1.1 - #compiling....................................................
Error running '__rvm_make -j4',
showing last 15 lines of /home/K/.rvm/log/1433355357_ruby-2.1.1/make.log
make[2]: Leaving directory '/home/K/.rvm/src/ruby-2.1.1/ext/-test-/printf'
exts.mk:109: recipe for target 'ext/-test-/printf/all' failed
make[1]: *** [ext/-test-/printf/all] Error 2
make[1]: *** Waiting for unfinished jobs....
installing default rational libraries
installing default recursion libraries
make[2]: Leaving directory '/home/K/.rvm/src/ruby-2.1.1/ext/-test-/postponed_job'
linking shared-object -test-/rational.so
linking shared-object -test-/recursion.so
make[2]: Leaving directory '/home/K/.rvm/src/ruby-2.1.1/ext/-test-/recursion'
make[2]: Leaving directory '/home/K/.rvm/src/ruby-2.1.1/ext/-test-/rational'
make[1]: Leaving directory '/home/K/.rvm/src/ruby-2.1.1'
uncommon.mk:180: recipe for target 'build-ext' failed
make: *** [build-ext] Error 2
++ return 2
There has been an error while running make. Halting the installation.

任何帮助将不胜感激。谢谢

Answer 1

您需要修补 ruby​​ 源代码，以便它可以在 cygwin 上编译。幸好 rvm 支持开箱即用的补丁！

创建一个名为cygwin.patch 的文件，其内容如下：

--- /ext/-test-/printf/printf.c 2014-06-29 10:17:20.000000000 -0700
+++ /ext/-test-/printf/printf.c 2015-07-08 16:58:15.882479100 -0700
@@ -1,3 +1,4 @@
+#define __STRICT_ANSI__ /* avoid conflicting utoa */
#include <ruby.h>
#include <ruby/encoding.h>

现在只需使用--patch 参数执行rvm，如下所示：

rvm install 2.2-head --patch cygwin.patch