[PATCH 1/2] Makefile: not use mismatched curl_config to check version

From: Jiang Xin <zhiyou.jx@alibaba-inc.com>

We may install different versions of curl, E.g.:

 * A system default curl, which version is below 7.34.0, is installed
   in "/usr", and the "curl_config" program is located in "/usr/bin/".

 * A higher version of curl is installed in "/opt/git/embedded/", and
   the "curl_config" program is located in "/opt/git/embedded/bin/".

If we add the path "/opt/git/embedded/bin" in search PATH, and install git using command "make && sudo make install", the source code may be compiled twice.

This is because when we run "make" using normal user account, make will call "/opt/git/embedded/bin/curl_config" to check curl version, and will set variable USE_CURL_FOR_IMAP_SEND. But when we call "make install" using root user's account, we call the system default version of curl_config to check curl version, and will lead to a different "GIT-CFLAGS" file, and will recompile all source code again.

Append "$(CURLDIR)/bin" before the "CURL_CONFIG" variable to use the specific "curl_config" program we want to check curl version, we will get the correct "CURL_CFLAGS" and "CURL_LDFLAGS" variables, and we can also have a stable "GIT-CFLAGS" file to prevent recompile when running "sudo make install".

Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
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 Makefile | 1 +
 1 file changed, 1 insertion(+)