Issue #10821 has been updated by Aman Gupta.

Backport changed from 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN to 2.0.0: UNKNOWN, 2.1: REQUIRED, 2.2: REQUIRED

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Bug #10821: mkmf.rb: Incorrect have_devel? test depending on run order
https://bugs.ruby-lang.org/issues/10821#change-51372

* Author: Joshua Peek
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.1.2p95 (2014-05-08 revision 45877) [x86_64-darwin14.0]
* Backport: 2.0.0: UNKNOWN, 2.1: REQUIRED, 2.2: REQUIRED
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have_devel? is usually lazily checked on the first call to try_do(). However, try_do() may be invoked within the scope of a with_ldflags or with_cflags block. If have_devel? is checked for the first time with altered test LDFLAGS or CFLAGS it may crash.

~~~
# extconf.rb
$LDFLAGS = "-L/custom/path/to/lib
try_ldflags "-Issl"
# try_ldflags -> try_link -> try_do -> have_devel (with incorrect $LDFLAG in scope)
~~~



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