How to break on access of a specific global variable in gdb? [duplicate]

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Can 开发者_开发问答I set a breakpoint on 'memory access' in GDB?

I want to trace how a specific variable is initialized,

can gdb do this kind of job?

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The gdb command watch <expr> sets a breakpoint on write, rwatch on read, and awatch on read or write. You can use them as you would with breakpoints, with two considerations:

• You can't use gdb expressions in them (like $esp+...)
• You need support for them. Software support is much, much slower than hardware. To find out if your gdb can use hardware watchpoints, see the output of show can-use-hw-watchpoints.