Issue #10210 has been reported by Ivailo Monev.

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Bug #10210: LDSHARED and  LDSHAREDXX set to null ('')
https://bugs.ruby-lang.org/issues/10210

* Author: Ivailo Monev
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: 1.9.3-p547, 2.1.2
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
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While attempting to build Ruby on custom linux setup versions from 1.9.3-p547 to 2.1.2 fail to build, setting LDSHARED to "gcc -shared" and LDSHAREDXX to "g++ -shared" kind of sorted the problem but I still see some messages in the build log like:

make[2]: o: Command not found
make[2]: [../../.ext/i686-linux/ripper.so] Error 127 (ignored)

I'm attaching the config.log. Also, I want to highlight that on this setup Busybox is used and during the configure step I see the following (stripped) message:

checking whether ELF binaries are produced... cat: invalid option -- 'e'
BusyBox v1.22.1 (2014-08-30 20:49:51 UTC) multi-call binary.
...
no





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