diff options
author | David Malcolm <dmalcolm@redhat.com> | 2018-08-17 21:56:21 +0000 |
---|---|---|
committer | David Malcolm <dmalcolm@redhat.com> | 2018-08-17 21:56:21 +0000 |
commit | 6d9274ce62fb7f0bdeda170656eb1383e18e7446 (patch) | |
tree | beb75700fa738bc1c04197dd61012336a42fd914 | |
parent | c56484a19fc94604c9381e5318b7cb1db3110db9 (diff) |
C++: -Wwrite-strings: use location of string constant
Consider:
extern int callee (const char *one, char *two, const char *three);
int test ()
{
return callee ("first", "second", "third");
}
for which -Wwrite-strings was emitting:
Wwrite-strings.C: In function 'int test()':
Wwrite-strings.C:10:44: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
10 | return callee ("first", "second", "third");
| ^
This patch fixes the warning so that it underlines the pertinent argument
at the callsite:
Wwrite-strings.C: In function 'int test()':
Wwrite-strings.C:10:27: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
10 | return callee ("first", "second", "third");
| ^~~~~~~~
Ideally we ought to also issue a "note" highlighting the pertinent
parameter within the decl, but that's not readily available, so I'm
saving it for another patch.
gcc/cp/ChangeLog:
* typeck.c (string_conv_p): Extract location from EXP and use it
in preference to input_location when issuing warnings.
gcc/testsuite/ChangeLog:
* g++.dg/conversion/Wwrite-strings.C: New test.
git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@263635 138bc75d-0d04-0410-961f-82ee72b054a4
-rw-r--r-- | gcc/cp/ChangeLog | 5 | ||||
-rw-r--r-- | gcc/cp/typeck.c | 10 | ||||
-rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
-rw-r--r-- | gcc/testsuite/g++.dg/conversion/Wwrite-strings.C | 24 |
4 files changed, 39 insertions, 4 deletions
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 0b695907cf1..d8be93089b4 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,8 @@ +2018-08-17 David Malcolm <dmalcolm@redhat.com> + + * typeck.c (string_conv_p): Extract location from EXP and use it + in preference to input_location when issuing warnings. + 2018-08-15 David Malcolm <dmalcolm@redhat.com> * call.c: Include "gcc-rich-location.h". diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c index 64b3d583356..8c13ae9b19b 100644 --- a/gcc/cp/typeck.c +++ b/gcc/cp/typeck.c @@ -2208,6 +2208,8 @@ string_conv_p (const_tree totype, const_tree exp, int warn) && !same_type_p (t, wchar_type_node)) return 0; + location_t loc = EXPR_LOC_OR_LOC (exp, input_location); + STRIP_ANY_LOCATION_WRAPPER (exp); if (TREE_CODE (exp) == STRING_CST) @@ -2230,13 +2232,13 @@ string_conv_p (const_tree totype, const_tree exp, int warn) if (warn) { if (cxx_dialect >= cxx11) - pedwarn (input_location, OPT_Wwrite_strings, + pedwarn (loc, OPT_Wwrite_strings, "ISO C++ forbids converting a string constant to %qT", totype); else - warning (OPT_Wwrite_strings, - "deprecated conversion from string constant to %qT", - totype); + warning_at (loc, OPT_Wwrite_strings, + "deprecated conversion from string constant to %qT", + totype); } return 1; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index ea1f1fa6061..b8677d729bc 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2018-08-17 David Malcolm <dmalcolm@redhat.com> + + * g++.dg/conversion/Wwrite-strings.C: New test. + 2018-08-17 Sandra Loosemore <sandra@codesourcery.com> Chung-Lin Tang <cltang@codesourcery.com> Xianmiao Qu <xianmiao_qu@c-sky.com> diff --git a/gcc/testsuite/g++.dg/conversion/Wwrite-strings.C b/gcc/testsuite/g++.dg/conversion/Wwrite-strings.C new file mode 100644 index 00000000000..f6dbb150699 --- /dev/null +++ b/gcc/testsuite/g++.dg/conversion/Wwrite-strings.C @@ -0,0 +1,24 @@ +// { dg-options "-fdiagnostics-show-caret" } + +/* Verify that -Wwrite-strings underlines the string literal in question. */ + +extern int callee (const char *one, char *two, const char *three); + +int test_1 () +{ + return callee ("first", "second", "third"); // { dg-warning "string constant to 'char\\*'" } + /* { dg-begin-multiline-output "" } + return callee ("first", "second", "third"); + ^~~~~~~~ + { dg-end-multiline-output "" } */ + // TODO: underline the pertinent param in the decl of callee +} + +char *test_2 (void) +{ + return "foo"; // { dg-warning "string constant to 'char\\*'" } + /* { dg-begin-multiline-output "" } + return "foo"; + ^~~~~ + { dg-end-multiline-output "" } */ +} |