aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorTobias Burnus <tobias@codesourcery.com>2020-12-11 16:43:06 +0000
committerTom Stellard <tstellar@redhat.com>2020-12-14 17:31:14 -0500
commit700baa009dc685a0adc5f94d258be4ae24742471 (patch)
treecc845ce47b9344db70e3fd8646c2ed007a87c97a
parent[KernelAddressSanitizer] Fix globals exclusion for indirect aliases (diff)
downloadllvm-project-700baa009dc685a0adc5f94d258be4ae24742471.tar.gz
llvm-project-700baa009dc685a0adc5f94d258be4ae24742471.tar.bz2
llvm-project-700baa009dc685a0adc5f94d258be4ae24742471.zip
[MC][ELF] Accept abbreviated form with sh_flags and sh_entsize
D73999 / commit 75af9da755721123e62b45cd0bc0c5e688a9722a added for LLVM 11 a check that sh_flags and sh_entsize (and sh_type) changes are an error, in line with GNU assembler. However, GNU assembler accepts and GCC generates an abbreviated form: while the first .section contains the flags and entsize, subsequent sections simply contain the name without repeating entsize or flags. Do likewise for better compatibility. See https://bugs.llvm.org/show_bug.cgi?id=48201 Reviewed By: jhenderson, MaskRay Differential Revision: https://reviews.llvm.org/D92052 (cherry picked from commit 1deff4009e0ae661b03682901bf6932297ce7ea1)
-rw-r--r--llvm/lib/MC/MCParser/ELFAsmParser.cpp7
-rw-r--r--llvm/test/MC/ELF/section-flags-changed.s3
-rw-r--r--llvm/test/MC/ELF/section-omitted-attributes.s11
3 files changed, 19 insertions, 2 deletions
diff --git a/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index e5ab13bc719d..fb8215ef2281 100644
--- a/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
@@ -644,10 +644,13 @@ EndStmt:
!(SectionName == ".eh_frame" && Type == ELF::SHT_PROGBITS))
Error(loc, "changed section type for " + SectionName + ", expected: 0x" +
utohexstr(Section->getType()));
- if (Section->getFlags() != Flags)
+ // Check that flags are used consistently. However, the GNU assembler permits
+ // to leave out in subsequent uses of the same sections; for compatibility,
+ // do likewise.
+ if ((Flags || Size || !TypeName.empty()) && Section->getFlags() != Flags)
Error(loc, "changed section flags for " + SectionName + ", expected: 0x" +
utohexstr(Section->getFlags()));
- if (Section->getEntrySize() != Size)
+ if ((Flags || Size || !TypeName.empty()) && Section->getEntrySize() != Size)
Error(loc, "changed section entsize for " + SectionName +
", expected: " + Twine(Section->getEntrySize()));
diff --git a/llvm/test/MC/ELF/section-flags-changed.s b/llvm/test/MC/ELF/section-flags-changed.s
index 65f52cc29a6d..d2964ef046d1 100644
--- a/llvm/test/MC/ELF/section-flags-changed.s
+++ b/llvm/test/MC/ELF/section-flags-changed.s
@@ -9,4 +9,7 @@ foo:
# CHECK: {{.*}}.s:[[# @LINE+1]]:1: error: changed section flags for .foo, expected: 0x6
.pushsection .foo,"a",@progbits
+# CHECK: {{.*}}.s:[[# @LINE+1]]:1: error: changed section flags for .foo, expected: 0x6
+.section .foo,"",@progbits
+
.pushsection .foo,"ax",@progbits
diff --git a/llvm/test/MC/ELF/section-omitted-attributes.s b/llvm/test/MC/ELF/section-omitted-attributes.s
new file mode 100644
index 000000000000..72b7c9121387
--- /dev/null
+++ b/llvm/test/MC/ELF/section-omitted-attributes.s
@@ -0,0 +1,11 @@
+# RUN: llvm-mc -triple=x86_64 %s -o - | FileCheck %s
+
+# If section flags and other attributes are omitted, don't error.
+
+# CHECK: .section .foo,"aM",@progbits,1
+
+.section .foo,"aM",@progbits,1
+
+.section .foo
+
+.pushsection .foo