From dfc976fa4888814a253627e2ebd2913d29cffd59 Mon Sep 17 00:00:00 2001 From: Joel Rosdahl Date: Wed, 6 Aug 2025 18:52:28 +0200 Subject: [PATCH] docs: Mention that #pragma once could be problematic with PCH Fixes #1615. --- doc/MANUAL.adoc | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/doc/MANUAL.adoc b/doc/MANUAL.adoc index e67b3589..b8f48a6f 100644 --- a/doc/MANUAL.adoc +++ b/doc/MANUAL.adoc @@ -1802,7 +1802,7 @@ directories: == Precompiled headers -Ccache has support for precompiled headers with GCC and Clang. However, you have +Ccache has limited support for precompiled headers with GCC and Clang. You have to do some things to make it work properly: * You must set <> to *pch_defines,time_macros*. @@ -1833,6 +1833,9 @@ be used (if available) or ccache will fall back to running the real compiler and increase the statistics counter "`Preprocessing failed`" (if the non-precompiled header file is not available). +Also, you might get into trouble if header files use `#pragma once` instead of +include guards. + == C++ modules -- 2.47.2