From bd3384dd449d68818573599201f66e7f7048174e Mon Sep 17 00:00:00 2001 From: Jelte Fennema-Nio Date: Sat, 17 Jan 2026 14:51:36 +0100 Subject: [PATCH v7 4/5] Support using StaticAssert macros in C++ StaticAssertExpr didn't work in MSVC C++. This adds a dedicated C++ definition which uses an inline lamdbda, that calls only the static assert. Since this results in empty lambda, the actual call will be removed by any compiler that does some optimization. --- src/include/c.h | 8 ++++++-- src/test/modules/test_cplusplusext/test_cplusplusext.cpp | 5 +++++ 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/src/include/c.h b/src/include/c.h index 9c54a67506d..0e4befb9e85 100644 --- a/src/include/c.h +++ b/src/include/c.h @@ -956,13 +956,17 @@ pg_noreturn extern void ExceptionalCondition(const char *conditionName, static_assert(condition, errmessage) #define StaticAssertStmt(condition, errmessage) \ do { static_assert(condition, errmessage); } while(0) -#ifdef HAVE_STATEMENT_EXPRESSIONS +#ifdef __cplusplus +/* C++11 lambdas provide a convenient way to use static_assert as an expression */ +#define StaticAssertExpr(condition, errmessage) \ + ((void) ([](){ static_assert(condition, errmessage); }(), 0)) +#elif defined(HAVE_STATEMENT_EXPRESSIONS) #define StaticAssertExpr(condition, errmessage) \ ((void) ({ static_assert(condition, errmessage); true; })) #else #define StaticAssertExpr(condition, errmessage) \ ((void) sizeof(struct { int static_assert_failure : (condition) ? 1 : -1; })) -#endif /* HAVE_STATEMENT_EXPRESSIONS */ +#endif /* diff --git a/src/test/modules/test_cplusplusext/test_cplusplusext.cpp b/src/test/modules/test_cplusplusext/test_cplusplusext.cpp index 48741f27949..bb9c310504e 100644 --- a/src/test/modules/test_cplusplusext/test_cplusplusext.cpp +++ b/src/test/modules/test_cplusplusext/test_cplusplusext.cpp @@ -24,6 +24,8 @@ PG_MODULE_MAGIC_EXT("test_cplusplusext", "1.2"); PG_FUNCTION_INFO_V1(test_cplusplus_add); } +StaticAssertDecl(sizeof(int32) == 4, "int32 should be 4 bytes"); + /* * Simple function that returns the sum of two integers. This verifies that * C++ extension modules can be loaded and called correctly at runtime. @@ -36,6 +38,9 @@ test_cplusplus_add(PG_FUNCTION_ARGS) RangeTblRef *node = makeNode(RangeTblRef); RangeTblRef *copy = copyObject(node); + StaticAssertStmt(sizeof(int32) == 4, "int32 should be 4 bytes"); + (void) StaticAssertExpr(sizeof(int64) == 8, "int64 should be 8 bytes"); + pfree(copy); pfree(node); -- 2.52.0