diff mbox series

[committed] libstdc++: Add nonnull to starts_with/ends_with/contains string members

Message ID 20220826152058.166976-1-jwakely@redhat.com
State New, archived
Headers
Series [committed] libstdc++: Add nonnull to starts_with/ends_with/contains string members |

Commit Message

Jonathan Wakely Aug. 26, 2022, 3:20 p.m. UTC 
  Tested powerpc64le-linux, pushed to trunk.

-- >8 --

Ideally this wouldn't be needed, because eventually these pointers all
get passed to either the basic_string_view(const CharT*) constructor, or
to basic_string_view::find(const CharT*), both of which already have the
attribute. But for that to work requires optimization, so that the null
value gets propagated through the call chain.

Adding it explicitly to each member that requires a non-null pointer
makes the diagnostics more reliable even without optimization. It's
better to give a diagnostic earlier anyway, at the actual problematic
call in the user's code.

libstdc++-v3/ChangeLog:

	* include/bits/basic_string.h (starts_with, ends_with, contains):
	Add nonnull attribute.
	* include/bits/cow_string.h (starts_with, ends_with, contains):
	Likewise.
	* include/std/string_view (starts_with, ends_with, contains):
	Likewise.
	* testsuite/21_strings/basic_string/operations/contains/nonnull.cc
	* testsuite/21_strings/basic_string/operations/ends_with/nonnull.cc
	* testsuite/21_strings/basic_string/operations/starts_with/nonnull.cc
	* testsuite/21_strings/basic_string_view/operations/contains/nonnull.cc
	* testsuite/21_strings/basic_string_view/operations/ends_with/nonnull.cc
	* testsuite/21_strings/basic_string_view/operations/starts_with/nonnull.cc
---
 libstdc++-v3/include/bits/basic_string.h             |  3 +++
 libstdc++-v3/include/bits/cow_string.h               |  3 +++
 libstdc++-v3/include/std/string_view                 |  3 +++
 .../basic_string/operations/contains/nonnull.cc      | 12 ++++++++++++
 .../basic_string/operations/ends_with/nonnull.cc     | 12 ++++++++++++
 .../basic_string/operations/starts_with/nonnull.cc   | 12 ++++++++++++
 .../basic_string_view/operations/contains/nonnull.cc | 12 ++++++++++++
 .../operations/ends_with/nonnull.cc                  | 12 ++++++++++++
 .../operations/starts_with/nonnull.cc                | 12 ++++++++++++
 9 files changed, 81 insertions(+)
 create mode 100644 libstdc++-v3/testsuite/21_strings/basic_string/operations/contains/nonnull.cc
 create mode 100644 libstdc++-v3/testsuite/21_strings/basic_string/operations/ends_with/nonnull.cc
 create mode 100644 libstdc++-v3/testsuite/21_strings/basic_string/operations/starts_with/nonnull.cc
 create mode 100644 libstdc++-v3/testsuite/21_strings/basic_string_view/operations/contains/nonnull.cc
 create mode 100644 libstdc++-v3/testsuite/21_strings/basic_string_view/operations/ends_with/nonnull.cc
 create mode 100644 libstdc++-v3/testsuite/21_strings/basic_string_view/operations/starts_with/nonnull.cc
diff mbox series

Patch

diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h
index b04fba95678..9d8b415302b 100644
--- a/libstdc++-v3/include/bits/basic_string.h
+++ b/libstdc++-v3/include/bits/basic_string.h
@@ -3400,6 +3400,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CXX11
       starts_with(_CharT __x) const noexcept
       { return __sv_type(this->data(), this->size()).starts_with(__x); }
 
+      [[__gnu__::__nonnull__]]
       constexpr bool
       starts_with(const _CharT* __x) const noexcept
       { return __sv_type(this->data(), this->size()).starts_with(__x); }
@@ -3412,6 +3413,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CXX11
       ends_with(_CharT __x) const noexcept
       { return __sv_type(this->data(), this->size()).ends_with(__x); }
 
+      [[__gnu__::__nonnull__]]
       constexpr bool
       ends_with(const _CharT* __x) const noexcept
       { return __sv_type(this->data(), this->size()).ends_with(__x); }
@@ -3426,6 +3428,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CXX11
       contains(_CharT __x) const noexcept
       { return __sv_type(this->data(), this->size()).contains(__x); }
 
+      [[__gnu__::__nonnull__]]
       constexpr bool
       contains(const _CharT* __x) const noexcept
       { return __sv_type(this->data(), this->size()).contains(__x); }
diff --git a/libstdc++-v3/include/bits/cow_string.h b/libstdc++-v3/include/bits/cow_string.h
index f16e33ac1ef..f5f03338eec 100644
--- a/libstdc++-v3/include/bits/cow_string.h
+++ b/libstdc++-v3/include/bits/cow_string.h
@@ -3012,6 +3012,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
       starts_with(_CharT __x) const noexcept
       { return __sv_type(this->data(), this->size()).starts_with(__x); }
 
+      [[__gnu__::__nonnull__]]
       bool
       starts_with(const _CharT* __x) const noexcept
       { return __sv_type(this->data(), this->size()).starts_with(__x); }
@@ -3024,6 +3025,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
       ends_with(_CharT __x) const noexcept
       { return __sv_type(this->data(), this->size()).ends_with(__x); }
 
+      [[__gnu__::__nonnull__]]
       bool
       ends_with(const _CharT* __x) const noexcept
       { return __sv_type(this->data(), this->size()).ends_with(__x); }
@@ -3038,6 +3040,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
       contains(_CharT __x) const noexcept
       { return __sv_type(this->data(), this->size()).contains(__x); }
 
+      [[__gnu__::__nonnull__]]
       bool
       contains(const _CharT* __x) const noexcept
       { return __sv_type(this->data(), this->size()).contains(__x); }
diff --git a/libstdc++-v3/include/std/string_view b/libstdc++-v3/include/std/string_view
index 30ff136b1cb..5b96ffeecd6 100644
--- a/libstdc++-v3/include/std/string_view
+++ b/libstdc++-v3/include/std/string_view
@@ -360,6 +360,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
       starts_with(_CharT __x) const noexcept
       { return !this->empty() && traits_type::eq(this->front(), __x); }
 
+      [[__gnu__::__nonnull__]]
       constexpr bool
       starts_with(const _CharT* __x) const noexcept
       { return this->starts_with(basic_string_view(__x)); }
@@ -377,6 +378,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
       ends_with(_CharT __x) const noexcept
       { return !this->empty() && traits_type::eq(this->back(), __x); }
 
+      [[__gnu__::__nonnull__]]
       constexpr bool
       ends_with(const _CharT* __x) const noexcept
       { return this->ends_with(basic_string_view(__x)); }
@@ -392,6 +394,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
       contains(_CharT __x) const noexcept
       { return this->find(__x) != npos; }
 
+      [[__gnu__::__nonnull__]]
       constexpr bool
       contains(const _CharT* __x) const noexcept
       { return this->find(__x) != npos; }
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/operations/contains/nonnull.cc b/libstdc++-v3/testsuite/21_strings/basic_string/operations/contains/nonnull.cc
new file mode 100644
index 00000000000..e987cb7d297
--- /dev/null
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/operations/contains/nonnull.cc
@@ -0,0 +1,12 @@ 
+// { dg-options "-std=gnu++23 -Wnonnull -O0" }
+// { dg-do compile { target c++23 } }
+
+#include <string>
+
+void
+test01(const std::string& s)
+{
+  s.contains((const char*)nullptr);  // { dg-warning "\\\[-Wnonnull" }
+  s.contains((char*)nullptr);	     // { dg-warning "\\\[-Wnonnull" }
+  s.contains(nullptr);		     // { dg-warning "\\\[-Wnonnull" }
+}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/operations/ends_with/nonnull.cc b/libstdc++-v3/testsuite/21_strings/basic_string/operations/ends_with/nonnull.cc
new file mode 100644
index 00000000000..1f2a156bace
--- /dev/null
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/operations/ends_with/nonnull.cc
@@ -0,0 +1,12 @@ 
+// { dg-options "-std=gnu++20 -Wnonnull -O0" }
+// { dg-do compile { target c++20 } }
+
+#include <string>
+
+void
+test01(const std::string& s)
+{
+  s.ends_with((const char*)nullptr);  // { dg-warning "\\\[-Wnonnull" }
+  s.ends_with((char*)nullptr);	      // { dg-warning "\\\[-Wnonnull" }
+  s.ends_with(nullptr);		      // { dg-warning "\\\[-Wnonnull" }
+}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/operations/starts_with/nonnull.cc b/libstdc++-v3/testsuite/21_strings/basic_string/operations/starts_with/nonnull.cc
new file mode 100644
index 00000000000..8514359c877
--- /dev/null
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/operations/starts_with/nonnull.cc
@@ -0,0 +1,12 @@ 
+// { dg-options "-std=gnu++20 -Wnonnull -O0" }
+// { dg-do compile { target c++20 } }
+
+#include <string>
+
+void
+test01(const std::string& s)
+{
+  s.starts_with((const char*)nullptr);  // { dg-warning "\\\[-Wnonnull" }
+  s.starts_with((char*)nullptr);	// { dg-warning "\\\[-Wnonnull" }
+  s.starts_with(nullptr);		// { dg-warning "\\\[-Wnonnull" }
+}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/contains/nonnull.cc b/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/contains/nonnull.cc
new file mode 100644
index 00000000000..c0d274f095b
--- /dev/null
+++ b/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/contains/nonnull.cc
@@ -0,0 +1,12 @@ 
+// { dg-options "-std=gnu++23 -Wnonnull -O0" }
+// { dg-do compile { target c++23 } }
+
+#include <string_view>
+
+void
+test01(std::string_view s)
+{
+  s.contains((const char*)nullptr);  // { dg-warning "\\\[-Wnonnull" }
+  s.contains((char*)nullptr);	     // { dg-warning "\\\[-Wnonnull" }
+  s.contains(nullptr);		     // { dg-warning "\\\[-Wnonnull" }
+}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/ends_with/nonnull.cc b/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/ends_with/nonnull.cc
new file mode 100644
index 00000000000..09a99978a37
--- /dev/null
+++ b/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/ends_with/nonnull.cc
@@ -0,0 +1,12 @@ 
+// { dg-options "-std=gnu++20 -Wnonnull -O0" }
+// { dg-do compile { target c++20 } }
+
+#include <string_view>
+
+void
+test01(std::string_view s)
+{
+  s.ends_with((const char*)nullptr);  // { dg-warning "\\\[-Wnonnull" }
+  s.ends_with((char*)nullptr);	      // { dg-warning "\\\[-Wnonnull" }
+  s.ends_with(nullptr);		      // { dg-warning "\\\[-Wnonnull" }
+}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/starts_with/nonnull.cc b/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/starts_with/nonnull.cc
new file mode 100644
index 00000000000..c47f1dae832
--- /dev/null
+++ b/libstdc++-v3/testsuite/21_strings/basic_string_view/operations/starts_with/nonnull.cc
@@ -0,0 +1,12 @@ 
+// { dg-options "-std=gnu++20 -Wnonnull -O0" }
+// { dg-do compile { target c++20 } }
+
+#include <string_view>
+
+void
+test01(std::string_view s)
+{
+  s.starts_with((const char*)nullptr);  // { dg-warning "\\\[-Wnonnull" }
+  s.starts_with((char*)nullptr);	// { dg-warning "\\\[-Wnonnull" }
+  s.starts_with(nullptr);		// { dg-warning "\\\[-Wnonnull" }
+}