Provide pkg-config modules for optional modules #666

1. 
   ysangkok commented at 6:45 pm on September 22, 2019: none

   pkg-config provides the option of having multiple modules per package. One can check for the existence of a module (% pkg-config --exists libsecp256k1; echo $?). If secp256k1 provided pkg-config modules for its optional modules like ECDH, one could check conveniently whether libsecp256k1 was built with ECDH, if one requires this.

   I can make a patch for this if you think it is a good idea, please provide feedback.

   Currently, libsecp256k1 provides just a single module:

   0$ pkg-config --print-provides libsecp256k1
   1libsecp256k1 = 0.1
   

2. 
   apoelstra commented at 5:35 pm on October 11, 2019: contributor

   What would be involved in this? Just a change to configure.ac?
3. 
   ysangkok commented at 11:24 pm on October 11, 2019: none

   @apoelstra See PR #675
4. 
   ysangkok commented at 10:23 pm on May 1, 2024: none

   Closing this since the linked PR has discussion which seems to suggest that this is not desired.
5. ysangkok closed this on May 1, 2024

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Contributors
ysangkok apoelstra