[lld] f8685a8 - [NFC][ELF] Wrap invokeELFT in do { } while (0) so it behaves as a function (#150119)

[via llvm-commits]

Author: Jessica Clarke
Date: 2025-07-27T00:20:55+01:00
New Revision: f8685a8533dd90d31ead8c631337a798012533e0

URL: https://github.com/llvm/llvm-project/commit/f8685a8533dd90d31ead8c631337a798012533e0
DIFF: https://github.com/llvm/llvm-project/commit/f8685a8533dd90d31ead8c631337a798012533e0.diff

LOG: [NFC][ELF] Wrap invokeELFT in do { } while (0) so it behaves as a function (#150119)

The current implementation is dangerous if used in contexts that need a
single statement, since invokeELFT(...); is in fact two statements, a
switch statement and an empty statement.

Added: 
    

Modified: 
    lld/ELF/Target.h

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Target.h b/lld/ELF/Target.h
index 93f15920bfedb..f4a6d83dafad2 100644
--- a/lld/ELF/Target.h
+++ b/lld/ELF/Target.h
@@ -338,21 +338,23 @@ inline uint64_t overwriteULEB128(uint8_t *bufLoc, uint64_t val) {
 #pragma clang diagnostic ignored "-Wgnu-zero-variadic-macro-arguments"
 #endif
 #define invokeELFT(f, ...)                                                     \
-  switch (ctx.arg.ekind) {                                                     \
-  case lld::elf::ELF32LEKind:                                                  \
-    f<llvm::object::ELF32LE>(__VA_ARGS__);                                     \
-    break;                                                                     \
-  case lld::elf::ELF32BEKind:                                                  \
-    f<llvm::object::ELF32BE>(__VA_ARGS__);                                     \
-    break;                                                                     \
-  case lld::elf::ELF64LEKind:                                                  \
-    f<llvm::object::ELF64LE>(__VA_ARGS__);                                     \
-    break;                                                                     \
-  case lld::elf::ELF64BEKind:                                                  \
-    f<llvm::object::ELF64BE>(__VA_ARGS__);                                     \
-    break;                                                                     \
-  default:                                                                     \
-    llvm_unreachable("unknown ctx.arg.ekind");                                 \
-  }
+  do {                                                                         \
+    switch (ctx.arg.ekind) {                                                   \
+    case lld::elf::ELF32LEKind:                                                \
+      f<llvm::object::ELF32LE>(__VA_ARGS__);                                   \
+      break;                                                                   \
+    case lld::elf::ELF32BEKind:                                                \
+      f<llvm::object::ELF32BE>(__VA_ARGS__);                                   \
+      break;                                                                   \
+    case lld::elf::ELF64LEKind:                                                \
+      f<llvm::object::ELF64LE>(__VA_ARGS__);                                   \
+      break;                                                                   \
+    case lld::elf::ELF64BEKind:                                                \
+      f<llvm::object::ELF64BE>(__VA_ARGS__);                                   \
+      break;                                                                   \
+    default:                                                                   \
+      llvm_unreachable("unknown ctx.arg.ekind");                               \
+    }                                                                          \
+  } while (0)
 
 #endif