Allow a '0' precision in format strings (as the man page says it is okay).
Fixes <rdar://problem/7700339>.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@97482 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/PrintfFormatString.cpp b/lib/Analysis/PrintfFormatString.cpp
index 6d6b370..46acc8a 100644
--- a/lib/Analysis/PrintfFormatString.cpp
+++ b/lib/Analysis/PrintfFormatString.cpp
@@ -69,18 +69,17 @@
UpdateOnReturn <const char*> UpdateBeg(Beg, I);
unsigned accumulator = 0;
+ bool hasDigits = false;
for ( ; I != E; ++I) {
char c = *I;
if (c >= '0' && c <= '9') {
- // Ignore '0' on the first character.
- if (c == '0' && I == Beg)
- break;
+ hasDigits = true;
accumulator += (accumulator * 10) + (c - '0');
continue;
}
- if (accumulator)
+ if (hasDigits)
return OptionalAmount(OptionalAmount::Constant, accumulator, Beg);
break;
@@ -118,9 +117,18 @@
return OptionalAmount(false);
}
+ assert(Amt.getHowSpecified() == OptionalAmount::Constant);
+
if (*I == '$') {
+ // Special case: '*0$', since this is an easy mistake.
+ if (Amt.getConstantAmount() == 0) {
+ H.HandleZeroPosition(Beg, I - Beg + 1);
+ return OptionalAmount(false);
+ }
+
const char *Tmp = Beg;
Beg = ++I;
+
return OptionalAmount(OptionalAmount::Arg, Amt.getConstantAmount() - 1,
Tmp);
}
@@ -182,6 +190,12 @@
}
if (Amt.getHowSpecified() == OptionalAmount::Constant && *(I++) == '$') {
+ // Special case: '%0$', since this is an easy mistake.
+ if (Amt.getConstantAmount() == 0) {
+ H.HandleZeroPosition(Start, I - Start);
+ return true;
+ }
+
FS.setArgIndex(Amt.getConstantAmount() - 1);
FS.setUsesPositionalArg();
// Update the caller's pointer if we decided to consume
@@ -190,12 +204,6 @@
return false;
}
- // Special case: '%0$', since this is an easy mistake.
- if (*I == '0' && (I+1) != E && *(I+1) == '$') {
- H.HandleZeroPosition(Start, I - Start + 2);
- return true;
- }
-
return false;
}
diff --git a/test/Sema/format-strings.c b/test/Sema/format-strings.c
index 21d3aec..4db775f 100644
--- a/test/Sema/format-strings.c
+++ b/test/Sema/format-strings.c
@@ -170,6 +170,8 @@
printf("%d", (long long) 10); // expected-warning{{conversion specifies type 'int' but the argument has type 'long long'}}
printf("%Lf\n", (long double) 1.0); // no-warning
printf("%f\n", (long double) 1.0); // expected-warning{{conversion specifies type 'double' but the argument has type 'long double'}}
+ // The man page says that a zero precision is okay.
+ printf("%.0Lf", (long double) 1.0); // no-warning
}
void test11(void *p, char *s) {
@@ -227,6 +229,7 @@
// FIXME: This is probably not portable everywhere.
void test_positional_arguments() {
printf("%0$", (int)2); // expected-warning{{position arguments in format strings start counting at 1 (not 0)}}
+ printf("%1$*0$d", (int) 2); // expected-warning{{position arguments in format strings start counting at 1 (not 0)}}
printf("%1$d", (int) 2); // no-warning
printf("%1$d", (int) 2, 2); // expected-warning{{data argument not used by format string}}
printf("%1$d%1$f", (int) 2); // expected-warning{{conversion specifies type 'double' but the argument has type 'int'}}