doc: set CC_FOR_BUILD when building on OpenBSD #19605

1. 
   fanquake commented at 8:33 AM on July 28, 2020: member

   Closes: #19559

   While #19559 has been fixed upstream, it makes sense to not only recommend using CC_FOR_BUILDhere until the fix is pulled in as part of our next libsecp update, but after discussing with Cory, he suggested we should be setting this on OpenBSD (which still has the an ancient GCC) regardless.

2. doc: set CC_FOR_BUILD when building on OpenBSD

   Closes: #19559
   
   While #19559 has been fixed upstream, it makes sense to not only
   recommend using `CC_FOR_BUILD`here  until the fix is pulled in as
   part of our next libsecp update, but after discussing with Cory,
   he suggested we should be setting this on OpenBSD (which still has
   the an ancient GCC) regardless.

   01cd24c226
3. fanquake added the label Docs on Jul 28, 2020
4. fanquake requested review from theuni on Jul 28, 2020
5. 
   real-or-random commented at 7:03 PM on July 28, 2020: member

   ACK 01cd24c22606408d5c0ac74c9a2c5d85eff77846 I looked at the diff (but can't test the instructions on OpenBSD)

   Setting CC_FOR_BUILD here is the certainly the right thing, because it avoids the ancient GCC entirely. The upstream fix would work too but autoconf will select the ancient GCC then (which is not a huge problem since it's only used in the precomputation step during compilation but I think we should still avoid it).

6. 
   laanwj commented at 2:13 PM on August 10, 2020: member

   Code review ACK 01cd24c22606408d5c0ac74c9a2c5d85eff77846 Can test on OpenBSD later.

7. fanquake merged this on Aug 10, 2020
8. fanquake closed this on Aug 10, 2020

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9. fanquake deleted the branch on Aug 10, 2020
10. sidhujag referenced this in commit d61eebb471 on Aug 10, 2020
11. 
    real-or-random commented at 2:45 PM on January 12, 2021: member

    https://github.com/bitcoin-core/secp256k1/pull/862 has just been merged, which will make setting CC_FOR_BUILD unnecessary (after the next update of the secp256k1 subtree). Not sure if we want to change the docs. It certainly does not hurt to set the variable. :shrug:

12. DrahtBot locked this on Aug 16, 2022

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