From d038ce48f1adebd6917a1cfb595efd6f93d613ff Mon Sep 17 00:00:00 2001 From: Andrew Burgess Date: Wed, 23 Jun 2021 22:55:16 +0100 Subject: [PATCH] gdb: fix invalid arg coercion when calling static member functions In this commit: commit 7022349d5c86bae74b49225515f42d2e221bd368 Date: Mon Sep 4 20:21:13 2017 +0100 Stop assuming no-debug-info functions return int A new if case was added to call_function_by_hand_dummy to decide if a function should be considered prototyped or not. Previously the code was structured like this: if (COND_1) ACTION_1 else if (COND_2) ACTION_2 else ACTION_3 With the new block the code now looks like this: if (COND_1) ACTION_1 if (NEW_COND) NEW_ACTION else if (COND_2) ACTION_2 else ACTION_3 Notice the new block was added as and 'if' not 'else if'. I'm running into a case where GDB executes ACTION_1 and then ACTION_2. Prior to the above commit GDB would only have executed ACTION_1. The actions in the code in question are trying to figure out if a function should be considered prototyped or not. When a function is not prototyped some arguments will be coerced, e.g. floats to doubles. The COND_1 / ACTION_1 are a very broad, any member function should be considered prototyped, however, after the above patch GDB is now executing the later ACTION_2 which checks to see if the function's type has the 'prototyped' flag set - this is not the case for the member functions I'm testing, and so GDB treats the function as unprototyped and casts the float argument to a double. I believe that adding the new check as 'if' rather than 'else if' was a mistake, and so in this commit I add in the missing 'else'. gdb/ChangeLog: * infcall.c (call_function_by_hand_dummy): Add missing 'else' when setting prototyped flag. gdb/testsuite/ChangeLog: * gdb.cp/method-call-in-c.cc (struct foo_type): Add static member function static_method. (global_var): New global. (main): Use new static_method to ensure it is compiled in. * gdb.cp/method-call-in-c.exp: Test calls to static member function. --- gdb/ChangeLog | 5 +++++ gdb/infcall.c | 4 ++-- gdb/testsuite/ChangeLog | 9 +++++++++ gdb/testsuite/gdb.cp/method-call-in-c.cc | 9 +++++++++ gdb/testsuite/gdb.cp/method-call-in-c.exp | 3 +++ 5 files changed, 28 insertions(+), 2 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1d10ae0f6c..9613e3e02c 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2021-06-25 Andrew Burgess + + * infcall.c (call_function_by_hand_dummy): Add missing 'else' when + setting prototyped flag. + 2021-06-25 Andrew Burgess * ada-lang.c (desc_bounds): Use '{}' instead of NULL to indicate diff --git a/gdb/infcall.c b/gdb/infcall.c index ca3347fbb9..40298fb131 100644 --- a/gdb/infcall.c +++ b/gdb/infcall.c @@ -1026,8 +1026,8 @@ call_function_by_hand_dummy (struct value *function, prototyped. Can we respect TYPE_VARARGS? Probably not. */ if (ftype->code () == TYPE_CODE_METHOD) prototyped = 1; - if (TYPE_TARGET_TYPE (ftype) == NULL && ftype->num_fields () == 0 - && default_return_type != NULL) + else if (TYPE_TARGET_TYPE (ftype) == NULL && ftype->num_fields () == 0 + && default_return_type != NULL) { /* Calling a no-debug function with the return type explicitly cast. Assume the function is prototyped, diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index b155c71f7c..9bf8e9ebcc 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2021-06-25 Andrew Burgess + + * gdb.cp/method-call-in-c.cc (struct foo_type): Add static member + function static_method. + (global_var): New global. + (main): Use new static_method to ensure it is compiled in. + * gdb.cp/method-call-in-c.exp: Test calls to static member + function. + 2021-06-25 Andrew Burgess PR gdb/27994 diff --git a/gdb/testsuite/gdb.cp/method-call-in-c.cc b/gdb/testsuite/gdb.cp/method-call-in-c.cc index 95f3f3c22d..846a9111ef 100644 --- a/gdb/testsuite/gdb.cp/method-call-in-c.cc +++ b/gdb/testsuite/gdb.cp/method-call-in-c.cc @@ -35,9 +35,16 @@ struct foo_type return *this; } + static int static_method (float f, baz_type b) + { + return b.a + b.b + b.c + (int) f; + } + int var = 120; }; +volatile int global_var; + int main (void) { @@ -48,5 +55,7 @@ main (void) foo += b; + global_var = foo.static_method (f, b); + return foo.func (b, f); /* Break here. */ } diff --git a/gdb/testsuite/gdb.cp/method-call-in-c.exp b/gdb/testsuite/gdb.cp/method-call-in-c.exp index 411ba6790b..5debc0e9a7 100644 --- a/gdb/testsuite/gdb.cp/method-call-in-c.exp +++ b/gdb/testsuite/gdb.cp/method-call-in-c.exp @@ -43,5 +43,8 @@ foreach_with_prefix lang { c++ c } { set result [expr $result + 3] gdb_test "print foo += b" \ " = \\((?:struct )?foo_type &\\) @${hex}: \\\{var = ${result}\\\}" + + gdb_test "print foo.static_method (f, b)" " = 4" + gdb_test "print foo_type::static_method (f, b)" " = 4" } } -- 2.34.1