| Summary: | gdb thinks an int is not an int | ||
|---|---|---|---|
| Product: | gdb | Reporter: | Hi-Angel <hi-angel> |
| Component: | c++ | Assignee: | Not yet assigned to anyone <unassigned> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | ssbssa, tromey |
| Priority: | P2 | ||
| Version: | 8.3 | ||
| Target Milestone: | 10.1 | ||
| Host: | Target: | ||
| Build: | Last reconfirmed: | ||
The master branch has been updated by Hannes Domani <ssbssa@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=60e22c1eacb0df32aeeeb78c53cfd46c53a3770f commit 60e22c1eacb0df32aeeeb78c53cfd46c53a3770f Author: Hannes Domani <ssbssa@yahoo.de> Date: Tue Mar 31 14:49:06 2020 +0200 Allow pointer arithmetic with integer references Considering these variables: int i = 3; int &iref = i; It's not possible to do any pointer arithmetic with iref: (gdb) p &i+iref Argument to arithmetic operation not a number or boolean. So this adds checks for references to integers in pointer arithmetic. gdb/ChangeLog: 2020-04-01 Hannes Domani <ssbssa@yahoo.de> PR gdb/24789 * eval.c (is_integral_or_integral_reference): New function. (evaluate_subexp_standard): Allow integer references in pointer arithmetic. gdb/testsuite/ChangeLog: 2020-04-01 Hannes Domani <ssbssa@yahoo.de> PR gdb/24789 * gdb.cp/misc.cc: Add integer reference variable. * gdb.cp/misc.exp: Add test. Fixed. |
# Steps to reproduce (in terms of terminal commands) $ cat -n test.cpp 1 #include <cstdio> 2 #include <utility> 3 4 using namespace std; 5 6 int main() { 7 pair<int,int> mypair = {10, 10}; 8 auto [myint1,myint2] = mypair; 9 char* ptr = nullptr; 10 printf("%p\n", ptr + myint1); 11 } $ g++ test.cpp -o a -g3 -O0 -std=c++17 $ gdb ./a Reading symbols from ./a... gdb λ br 10 Breakpoint 1 at 0x11a6: file test.cpp, line 10. gdb λ r Starting program: /tmp/a Breakpoint 1, main () at test.cpp:10 10 printf("%p\n", ptr + myint1); gdb λ p ptr + myint1 # Expected $1 = 0xa <error: Cannot access memory at address 0xa> # Actual Argument to arithmetic operation not a number or boolean. # Possible workarounds Explicitly casting the int to int makes it work: gdb λ p ptr + (int)myint1 $1 = 0xa <error: Cannot access memory at address 0xa>