String literals in asm files: use asm quoting conventions, not OCaml's#588
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xavierleroy wants to merge 1 commit into
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String literals in asm files: use asm quoting conventions, not OCaml's#588xavierleroy wants to merge 1 commit into
xavierleroy wants to merge 1 commit into
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Currently, we use the `%S` format of Printf.printf to emit some string literals in assembly files: filenames in `.file` directives, and `.asciz` directives for DWARF debug information. (String literals coming from C source files follow a different path that doesn't use `%S`. They are not affected by the problem fixed in this commit.) The `%S` format produces an OCaml string literal, which can be misinterpreted by the GNU and Diab assemblers. In particular, OCaml uses decimal escapes `\ddd` (three decimal digits) while assemblers, like C, use octal escapes `\ooo` (three octal digits). Consequently, a "vertical tab" character (ASCII 0x0B) is printed as `\011`, which is interpreted as "horizontal tab" (ASCII 0x09) by the assembler. This commits introduces `PrintAsmaux.quote_string` to produce a string literal in asm / C syntax, with octal escape sequences, and uses it in assembler printers in place of `%S`.
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Currently, we use the
%Sformat ofPrintf.printfto emit some string literals in assembly files: filenames in.filedirectives, and.ascizdirectives for DWARF debug information.(String literals coming from C source files follow a different path that doesn't use
%S. They are not affected by the problem fixed in this commit.)The
%Sformat produces an OCaml string literal, which can be misinterpreted by the GNU and Diab assemblers. In particular, OCaml uses decimal escapes\ddd(three decimal digits) while assemblers, like C, use octal escapes\ooo(three octal digits). Consequently, a "vertical tab" character (ASCII 0x0B) is printed as\011, which is interpreted as "horizontal tab" (ASCII 0x09) by the assembler.This commits introduces
PrintAsmaux.quote_stringto produce a string literal in asm / C syntax, with octal escape sequences, and uses it in assembler printers in place of%S.