From 505da0262c1713afb0b700c1673dbbd882265d1f Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Fri, 10 Jan 2025 09:01:00 +0100 Subject: [PATCH v2 3/3] Add a bit of documentation related to IWYU Add some basic information about IWYU to src/tools/pginclude/README. Discussion: https://www.postgresql.org/message-id/flat/9395d484-eff4-47c2-b276-8e228526c8ae@eisentraut.org --- src/tools/pginclude/README | 42 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/src/tools/pginclude/README b/src/tools/pginclude/README index 007d0397e79..2f8fe6b78ba 100644 --- a/src/tools/pginclude/README +++ b/src/tools/pginclude/README @@ -1,5 +1,47 @@ src/tools/pginclude/README +This directory contains some scripts and information for managing +header files and includes in PostgreSQL source code. + + +include-what-you-use +==================== + +include-what-you-use (IWYU) () is a +tool for finding missing or superfluous includes in C source files. + +With a compilation database (compile_commands.json, produced by +meson), it can be run like this, over the whole source tree: + + iwyu_tool.py -p build . + +(this will likely be very noisy) or for individual files: + + iwyu_tool.py -p build src/bin/psql/startup.c + +Various other invocation options are available. + +It is recommended to use at least version 0.23. Earlier versions give +advice that is incompatible with the compiler warning option +-Wmissing-variable-declarations. + +clangd (the language server) can automatically give IWYU-style advice; +see . + +The source code contains some "IWYU pragma" comments to tell IWYU +about some PostgreSQL include file conventions (such as that a header +such as "postgres.h" should always be included, even if it doesn't +contribute any symbols used by the particular source file) and to +silence a few warnings that are difficult to fix. See + +for documentation about those. + +Of course, any include changes suggested by this or other tools should +be checked and verified carefully. Note that some includes are only +used on some platforms or with some compilation options, so blindly +following the produced advice is not recommended. + + headerscheck ============ -- 2.47.1