[clang] 12411c1 - [clang][bytecode] 0 bitwidth IntAP values also use one word (#193224)

[via cfe-commits]

Author: Timm Baeder
Date: 2026-04-23T12:51:21+02:00
New Revision: 12411c1e6ac577e4144aa541c3c4be87dff68d2a

URL: https://github.com/llvm/llvm-project/commit/12411c1e6ac577e4144aa541c3c4be87dff68d2a
DIFF: https://github.com/llvm/llvm-project/commit/12411c1e6ac577e4144aa541c3c4be87dff68d2a.diff

LOG: [clang][bytecode] 0 bitwidth IntAP values also use one word (#193224)

Not 0. This can happen in error cases.

Added: 
    

Modified: 
    clang/lib/AST/ByteCode/IntegralAP.h
    clang/test/AST/ByteCode/intap.cpp

Removed: 
    


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diff  --git a/clang/lib/AST/ByteCode/IntegralAP.h b/clang/lib/AST/ByteCode/IntegralAP.h
index 9f53ac7716bbaa..061038cde70817 100644
--- a/clang/lib/AST/ByteCode/IntegralAP.h
+++ b/clang/lib/AST/ByteCode/IntegralAP.h
@@ -138,7 +138,7 @@ template <bool Signed> class IntegralAP final {
 
   constexpr uint32_t bitWidth() const { return BitWidth; }
   constexpr unsigned numWords() const { return APInt::getNumWords(BitWidth); }
-  constexpr bool singleWord() const { return numWords() == 1; }
+  constexpr bool singleWord() const { return numWords() <= 1; }
   constexpr static bool isNumber() { return true; }
 
   APSInt toAPSInt(unsigned Bits = 0) const {

diff  --git a/clang/test/AST/ByteCode/intap.cpp b/clang/test/AST/ByteCode/intap.cpp
index 804b16484ca01d..5c3e9f979e1292 100644
--- a/clang/test/AST/ByteCode/intap.cpp
+++ b/clang/test/AST/ByteCode/intap.cpp
@@ -69,6 +69,10 @@ constexpr _BitInt(32) nope = top / bottom;  // both-error {{must be initialized
 constexpr _BitInt(32) noooo = top % bottom; // both-error {{must be initialized by a constant expression}} \
                                             // both-note {{value 2147483648 is outside the range}}
 
+struct {
+  _BitInt(35) void : 33; // both-error {{cannot combine with previous '_BitInt' declaration specifier}}
+} s;
+
 namespace APCast {
   constexpr _BitInt(10) A = 1;
   constexpr _BitInt(11) B = A;