[lld] Fix -ObjC load behavior with LTO for section names with whitespace (#146654)

This is a fix additional to #92162

In some cases, section names contain a whitespace between the segment
name and the actual section name (e.g. `__TEXT, __swift5_proto`). It is
confirmed by source code of the Swift compiler

This fix allows LTO to work correctly with the `-ObjC` flag in that rare
case when only a section with a whitespace in the name is present in the
linked bitcode module, but there are no sections containing
`__TEXT,__swift`

---------

Co-authored-by: Ураков Александр Сергеевич <a.urakov@tbank.ru>
Co-authored-by: Ellis Hoag <ellis.sparky.hoag@gmail.com>
This commit is contained in:
Aleksandr Urakov 2025-07-21 09:08:33 +03:00 committed by GitHub
parent 6193dd5553
commit c9cbd4e9d4
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 26 additions and 8 deletions

View File

@ -7,12 +7,13 @@
# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/has-swift.s -o %t/has-swift.o
# RUN: llvm-as %t/has-swift-ir-loaded.ll -o %t/has-swift-ir-loaded.o
# RUN: llvm-as %t/has-swift-ir-not-loaded.ll -o %t/has-swift-ir-not-loaded.o
# RUN: llvm-as %t/has-swift-with-space-ir-loaded.ll -o %t/has-swift-with-space-ir-loaded.o
# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/has-swift-proto.s -o %t/has-swift-proto.o
# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/no-objc.s -o %t/no-objc.o
## Make sure we don't mis-parse a 32-bit file as 64-bit
# RUN: llvm-mc -filetype=obj -triple=armv7-apple-watchos %t/no-objc.s -o %t/wrong-arch.o
# RUN: llvm-ar rcs %t/libHasSomeObjC.a %t/no-objc.o %t/has-objc-symbol.o %t/has-objc-category.o %t/has-swift.o %t/has-swift-proto.o %t/has-swift-ir-loaded.o %t/has-swift-ir-not-loaded.o %t/wrong-arch.o
# RUN: llvm-ar rcs %t/libHasSomeObjC2.a %t/no-objc.o %t/has-objc-symbol-and-category.o %t/has-swift.o %t/has-swift-proto.o %t/has-swift-ir-loaded.o %t/has-swift-ir-not-loaded.o %t/wrong-arch.o
# RUN: llvm-ar rcs %t/libHasSomeObjC.a %t/no-objc.o %t/has-objc-symbol.o %t/has-objc-category.o %t/has-swift.o %t/has-swift-proto.o %t/has-swift-ir-loaded.o %t/has-swift-ir-not-loaded.o %t/has-swift-with-space-ir-loaded.o %t/wrong-arch.o
# RUN: llvm-ar rcs %t/libHasSomeObjC2.a %t/no-objc.o %t/has-objc-symbol-and-category.o %t/has-swift.o %t/has-swift-proto.o %t/has-swift-ir-loaded.o %t/has-swift-ir-not-loaded.o %t/has-swift-with-space-ir-loaded.o %t/wrong-arch.o
# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/test.s -o %t/test.o
@ -22,7 +23,7 @@
# RUN: %lld -lSystem %t/test.o -o %t/test -L%t -lHasSomeObjC2 -ObjC
# RUN: llvm-objdump --section-headers --syms %t/test | FileCheck %s --check-prefix=OBJC
# RUN: %no-fatal-warnings-lld -lSystem %t/test.o -o %t/test --start-lib %t/no-objc.o %t/has-objc-symbol.o %t/has-objc-category.o %t/has-swift.o %t/has-swift-proto.o %t/has-swift-ir-loaded.o %t/has-swift-ir-not-loaded.o %t/wrong-arch.o --end-lib -ObjC 2>&1 \
# RUN: %no-fatal-warnings-lld -lSystem %t/test.o -o %t/test --start-lib %t/no-objc.o %t/has-objc-symbol.o %t/has-objc-category.o %t/has-swift.o %t/has-swift-proto.o %t/has-swift-ir-loaded.o %t/has-swift-ir-not-loaded.o %t/has-swift-with-space-ir-loaded.o %t/wrong-arch.o --end-lib -ObjC 2>&1 \
# RUN: | FileCheck -check-prefix=WARNING %s
# RUN: llvm-objdump --section-headers --syms %t/test | FileCheck %s --check-prefix=OBJC
@ -34,14 +35,16 @@
# OBJC-NEXT: 0 __text {{.*}} TEXT
# OBJC-NEXT: 1 __swift {{.*}} DATA
# OBJC-NEXT: 2 __swift5_fieldmd{{.*}} DATA
# OBJC-NEXT: 3 __objc_catlist {{.*}} DATA
# OBJC-NEXT: 4 has_objc_symbol {{.*}} DATA
# OBJC-NEXT: 3 __swift5_proto {{.*}} DATA
# OBJC-NEXT: 4 __objc_catlist {{.*}} DATA
# OBJC-NEXT: 5 has_objc_symbol {{.*}} DATA
# OBJC-EMPTY:
# OBJC-NEXT: SYMBOL TABLE:
# OBJC-DAG: g O __TEXT,__swift _foo
# OBJC-DAG: g F __TEXT,__text _main
# OBJC-DAG: g F __TEXT,__text _OBJC_CLASS_$_MyObject
# OBJC-DAG: g O __TEXT,__swift5_fieldmd $s7somelib4Blah_pMF
# OBJC-DAG: g O __TEXT,__swift5_proto _baz
# RUN: %lld -lSystem %t/test.o -o %t/test -L%t -lHasSomeObjC
# RUN: llvm-objdump --section-headers --syms %t/test | FileCheck %s --check-prefix=NO-OBJC
@ -117,6 +120,13 @@ target triple = "x86_64-apple-darwin"
@bar = global i64 1234
@llvm.used = appending global [1 x ptr] [ptr @bar]
#--- has-swift-with-space-ir-loaded.ll
target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
target triple = "x86_64-apple-darwin"
@baz = global i64 1234, section "__TEXT, __swift5_proto"
@llvm.used = appending global [1 x ptr] [ptr @baz]
#--- has-swift-proto.s
.section __TEXT,__swift5_fieldmd
.globl $s7somelib4Blah_pMF

View File

@ -293,10 +293,18 @@ static Expected<bool> hasObjCCategoryInModule(BitstreamCursor &Stream) {
std::string S;
if (convertToString(Record, 0, S))
return error("Invalid section name record");
// Check for the i386 and other (x86_64, ARM) conventions
if (S.find("__DATA,__objc_catlist") != std::string::npos ||
S.find("__OBJC,__category") != std::string::npos ||
S.find("__TEXT,__swift") != std::string::npos)
auto [Segment, Section] = StringRef(S).split(",");
Segment = Segment.trim();
Section = Section.trim();
if (Segment == "__DATA" && Section.starts_with("__objc_catlist"))
return true;
if (Segment == "__OBJC" && Section.starts_with("__category"))
return true;
if (Segment == "__TEXT" && Section.starts_with("__swift"))
return true;
break;
}