Description:
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libcurl has libs.private in its pkg-config configuration. When attempting to statically compile curl + mbedtls with PHP, the compile process fails because statically linked libraries are not included in the configure. ext/curl does not include the necessary --static flag when calling pkg-config for libcurl.

I'm trying to build curl with mbedtls support and pkg-config statically, and the build fails because mbedtls is not linked against.

I have been working around this by forcing usage of curl-config, which works as expected.

Expected result:
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PHP should be able to compile successfully with statically compiled and linked curl + mbedtls

Actual result:
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compile failure.