commit be6126a2a784e1446460b8d15c2b26f880c871fc
author Hans Wennborg <hans@hanshq.net> Wed Feb 15 09:59:46 2012 +0000
committer Hans Wennborg <hans@hanshq.net> Wed Feb 15 09:59:46 2012 +0000
tree dcd82b29009df602ff45a73ab58053e9e883d25a
parent 37ce0104b182c9410cf2a76fe5a63a81dac876ac

Make -Wformat fix-its preserve original conversion specifiers.

This commit makes PrintfSpecifier::fixType() and ScanfSpecifier::fixType()
only fix a conversion specification enough that Clang wouldn't warn about it,
as opposed to always changing it to use the "canonical" conversion specifier.
(PR11975)

This preserves the user's choice of conversion specifier in cases like:

printf("%a", (long double)1);
where we previously suggested "%Lf", we now suggest "%La"

printf("%x", (long)1);
where we previously suggested "%ld", we now suggest "%lx".

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150578 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/PrintfFormatString.cpp

diff --git a/lib/Analysis/PrintfFormatString.cpp b/lib/Analysis/PrintfFormatString.cpp
index 6da37fc..ff0174e 100644
--- a/lib/Analysis/PrintfFormatString.cpp
+++ b/lib/Analysis/PrintfFormatString.cpp
@@ -336,7 +336,8 @@
   return ArgTypeResult();
 }
 
-bool PrintfSpecifier::fixType(QualType QT, const LangOptions &LangOpt) {
+bool PrintfSpecifier::fixType(QualType QT, const LangOptions &LangOpt,
+                              ASTContext &Ctx, bool IsObjCLiteral) {
   // Handle strings first (char *, wchar_t *)
   if (QT->isPointerType() && (QT->getPointeeType()->isAnyCharacterType())) {
     CS.setKind(ConversionSpecifier::sArg);
@@ -432,6 +433,11 @@
     }
   }
 
+  // If fixing the length modifier was enough, we are done.
+  const analyze_printf::ArgTypeResult &ATR = getArgType(Ctx, IsObjCLiteral);
+  if (hasValidLengthModifier() && ATR.isValid() && ATR.matchesType(Ctx, QT))
+    return true;
+
   // Set conversion specifier and disable any flags which do not apply to it.
   // Let typedefs to char fall through to int, as %c is silly for uint8_t.
   if (isa<TypedefType>(QT) && QT->isAnyCharacterType()) {
@@ -451,9 +457,7 @@
     HasAlternativeForm = 0;
   }
   else if (QT->isUnsignedIntegerType()) {
-    // Preserve the original formatting, e.g. 'X', 'o'.
-    if (!cast<PrintfConversionSpecifier>(CS).isUIntArg())
-      CS.setKind(ConversionSpecifier::uArg);
+    CS.setKind(ConversionSpecifier::uArg);
     HasAlternativeForm = 0;
     HasPlusPrefix = 0;
   } else {

lib/Analysis/ScanfFormatString.cpp

diff --git a/lib/Analysis/ScanfFormatString.cpp b/lib/Analysis/ScanfFormatString.cpp
index c1cdef8..5990a56 100644
--- a/lib/Analysis/ScanfFormatString.cpp
+++ b/lib/Analysis/ScanfFormatString.cpp
@@ -307,8 +307,8 @@
   return ScanfArgTypeResult();
 }
 
-bool ScanfSpecifier::fixType(QualType QT, const LangOptions &LangOpt)
-{
+bool ScanfSpecifier::fixType(QualType QT, const LangOptions &LangOpt,
+                             ASTContext &Ctx) {
   if (!QT->isPointerType())
     return false;
 
@@ -390,17 +390,19 @@
     }
   }
 
+  // If fixing the length modifier was enough, we are done.
+  const analyze_scanf::ScanfArgTypeResult &ATR = getArgType(Ctx);
+  if (hasValidLengthModifier() && ATR.isValid() && ATR.matchesType(Ctx, QT))
+    return true;
+
   // Figure out the conversion specifier.
   if (PT->isRealFloatingType())
     CS.setKind(ConversionSpecifier::fArg);
   else if (PT->isSignedIntegerType())
     CS.setKind(ConversionSpecifier::dArg);
-  else if (PT->isUnsignedIntegerType()) {
-    // Preserve the original formatting, e.g. 'X', 'o'.
-    if (!CS.isUIntArg()) {
-      CS.setKind(ConversionSpecifier::uArg);
-    }
-  } else
+  else if (PT->isUnsignedIntegerType())
+    CS.setKind(ConversionSpecifier::uArg);
+  else
     llvm_unreachable("Unexpected type");
 
   return true;

lib/Sema/SemaChecking.cpp

diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 3393cf7..1d75ef6 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -2181,7 +2181,8 @@
 
     // We may be able to offer a FixItHint if it is a supported type.
     PrintfSpecifier fixedFS = FS;
-    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions());
+    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions(),
+                                   S.Context, IsObjCLiteral);
 
     if (success) {
       // Get the fix string from the fixed format specifier
@@ -2340,7 +2341,8 @@
   const analyze_scanf::ScanfArgTypeResult &ATR = FS.getArgType(S.Context);
   if (ATR.isValid() && !ATR.matchesType(S.Context, Ex->getType())) {
     ScanfSpecifier fixedFS = FS;
-    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions());
+    bool success = fixedFS.fixType(Ex->getType(), S.getLangOptions(),
+                                   S.Context);
 
     if (success) {
       // Get the fix string from the fixed format specifier.