[clang] 128f7da - [Lex] Use line markers in preprocessed assembly predefines file
John Brawn via cfe-commits
cfe-commits at lists.llvm.org
Tue Mar 7 08:21:20 PST 2023
Author: John Brawn
Date: 2023-03-07T16:20:43Z
New Revision: 128f7dac82ea4b996ddfd0db86edfdac4013b1da
URL: https://github.com/llvm/llvm-project/commit/128f7dac82ea4b996ddfd0db86edfdac4013b1da
DIFF: https://github.com/llvm/llvm-project/commit/128f7dac82ea4b996ddfd0db86edfdac4013b1da.diff
LOG: [Lex] Use line markers in preprocessed assembly predefines file
GNU line marker directives are not recognised when preprocessing
assembly files, meaning they can't be used in the predefines file
meaning macros defined on the command line are reported as being
built-in.
Change this to permit line markers but only in the predefines file,
so we can correctly report command line macros as coming from the
command line.
Differential Revision: https://reviews.llvm.org/D145397
Added:
clang/test/Preprocessor/directives_asm.S
clang/test/Preprocessor/macro_redefined.S
Modified:
clang/docs/ReleaseNotes.rst
clang/lib/Frontend/InitPreprocessor.cpp
clang/lib/Lex/PPDirectives.cpp
Removed:
################################################################################
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 4bc2e54a85998..59c8c5c799f1a 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -159,6 +159,9 @@ Improvements to Clang's diagnostics
class if that class was first introduced with a forward declaration.
- Diagnostic notes and fix-its are now generated for ``ifunc``/``alias`` attributes
which point to functions whose names are mangled.
+- Diagnostics relating to macros on the command line of a preprocessed assembly
+ file are now reported as coming from the file ``<command line>`` instead of
+ ``<built-in>``.
Bug Fixes in This Version
-------------------------
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp
index 208c6a8db1598..ab00724af2fa9 100644
--- a/clang/lib/Frontend/InitPreprocessor.cpp
+++ b/clang/lib/Frontend/InitPreprocessor.cpp
@@ -1317,11 +1317,10 @@ void clang::InitializePreprocessor(
llvm::raw_string_ostream Predefines(PredefineBuffer);
MacroBuilder Builder(Predefines);
- // Emit line markers for various builtin sections of the file. We don't do
- // this in asm preprocessor mode, because "# 4" is not a line marker directive
- // in this mode.
- if (!PP.getLangOpts().AsmPreprocessor)
- Builder.append("# 1 \"<built-in>\" 3");
+ // Emit line markers for various builtin sections of the file. The 3 here
+ // marks <built-in> as being a system header, which suppresses warnings when
+ // the same macro is defined multiple times.
+ Builder.append("# 1 \"<built-in>\" 3");
// Install things like __POWERPC__, __GNUC__, etc into the macro table.
if (InitOpts.UsePredefines) {
@@ -1359,8 +1358,7 @@ void clang::InitializePreprocessor(
// Add on the predefines from the driver. Wrap in a #line directive to report
// that they come from the command line.
- if (!PP.getLangOpts().AsmPreprocessor)
- Builder.append("# 1 \"<command line>\" 1");
+ Builder.append("# 1 \"<command line>\" 1");
// Process #define's and #undef's in the order they are given.
for (unsigned i = 0, e = InitOpts.Macros.size(); i != e; ++i) {
@@ -1372,8 +1370,7 @@ void clang::InitializePreprocessor(
}
// Exit the command line and go back to <built-in> (2 is LC_LEAVE).
- if (!PP.getLangOpts().AsmPreprocessor)
- Builder.append("# 1 \"<built-in>\" 2");
+ Builder.append("# 1 \"<built-in>\" 2");
// If -imacros are specified, include them now. These are processed before
// any -include directives.
diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index 9e2392529ff53..bda9d0877612e 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -1185,8 +1185,12 @@ void Preprocessor::HandleDirective(Token &Result) {
CurPPLexer->getConditionalStackDepth() > 0);
return;
case tok::numeric_constant: // # 7 GNU line marker directive.
- if (getLangOpts().AsmPreprocessor)
- break; // # 4 is not a preprocessor directive in .S files.
+ // In a .S file "# 4" may be a comment so don't treat it as a preprocessor
+ // directive. However do permit it in the predefines file, as we use line
+ // markers to mark the builtin macros as being in a system header.
+ if (getLangOpts().AsmPreprocessor &&
+ SourceMgr.getFileID(SavedHash.getLocation()) != getPredefinesFileID())
+ break;
return HandleDigitDirective(Result);
default:
IdentifierInfo *II = Result.getIdentifierInfo();
diff --git a/clang/test/Preprocessor/directives_asm.S b/clang/test/Preprocessor/directives_asm.S
new file mode 100644
index 0000000000000..55e71d621e341
--- /dev/null
+++ b/clang/test/Preprocessor/directives_asm.S
@@ -0,0 +1,25 @@
+// RUN: %clang -c %s -o /dev/null 2>&1 | FileCheck %s
+
+// Check that preprocessor directives are recognised as such, but lines starting
+// with a # that aren't directives are instead treated as comments.
+
+#define MACRO .warning "This is a macro"
+ MACRO
+
+// CHECK: directives_asm.S:7:9: warning: This is a macro
+
+#not a preprocessing directive
+
+// CHECK-NOT: error: invalid preprocessing directive
+
+# 100
+
+ .warning "line number should not change"
+
+// CHECK: directives_asm.S:17:9: warning: line number should not change
+
+#line 100
+
+ .warning "line number should change"
+
+// CHECK: directives_asm.S:101:9: warning: line number should change
diff --git a/clang/test/Preprocessor/macro_redefined.S b/clang/test/Preprocessor/macro_redefined.S
new file mode 100644
index 0000000000000..9e3d5b08cbb2b
--- /dev/null
+++ b/clang/test/Preprocessor/macro_redefined.S
@@ -0,0 +1,10 @@
+// RUN: %clang %s -E -DCLI_MACRO=1 2>&1 | FileCheck %s
+
+#define CLI_MACRO
+// CHECK: macro_redefined.S{{.+}}: warning: 'CLI_MACRO' macro redefined
+// CHECK: <command line>{{.+}}: note: previous definition is here
+
+#define REGULAR_MACRO
+#define REGULAR_MACRO 1
+// CHECK: macro_redefined.S{{.+}}: warning: 'REGULAR_MACRO' macro redefined
+// CHECK: macro_redefined.S{{.+}}: note: previous definition is here
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