[PATCH v2 1/3] git-compat-util: introduce BUG_IF_NOT() macro

From: Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>
Date: Mar 16, 2025, 06:42 UTC
Message-ID: <109060ccb8665c73aa0c4f73e3cbbddcd135bde4.1742107322.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.1881.v2.git.1742107322.gitgitgadget@gmail.com>

From: Elijah Newren <newren@gmail.com>

Create a BUG_IF_NOT() macro which is similar to assert(), but will not be compiled out when NDEBUG is defined, and is thus safe to use even if its argument has side-effects.

We will use this new macro in a subsequent commit to convert a few existing assert() invocations to BUG_IF_NOT(). In particular, we'll convert the handful of invocations which cannot be proven to be free of side effects with a simple compiler/linker hack.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
 git-compat-util.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/git-compat-util.h b/git-compat-util.h
index e123288e8f1..c3415ad7e0a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1460,6 +1460,7 @@ extern int bug_called_must_BUG;
 __attribute__((format (printf, 3, 4))) NORETURN
 void BUG_fl(const char *file, int line, const char *fmt, ...);
 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
+#define BUG_IF_NOT(a) if (!(a)) BUG("Assertion `" #a "' failed.")
 __attribute__((format (printf, 3, 4)))
 void bug_fl(const char *file, int line, const char *fmt, ...);
 #define bug(...) bug_fl(__FILE__, __LINE__, __VA_ARGS__)

-- 
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