shithub: rgbds

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Have `jr` offset wrap with 16 bits
Overflow with `int16_t` is defined to two's complement so it's OK
This could trigger when jumping from the top of ROM0 to HRAM

--- a/src/link/patch.c

+++ b/src/link/patch.c

@@ -299,11 +299,11 @@

 		struct Patch *patch = &section->patches[patchID];

 		int32_t value = computeRPNExpr(patch, section);

+		/* `jr` is quite unlike the others... */

 		if (patch->type == PATCHTYPE_JR) {

-			/* `jr` is quite unlike the others... */

-			uint16_t address = section->org + patch->offset;

 			/* Target is relative to the byte *after* the operand */

-			int32_t offset = value - (address + 1);

+			uint16_t address = section->org + patch->offset + 1;

+			int16_t offset = value - address;

 			if (offset < -128 || offset > 127)

 				errx(1, "%s(%d): jr target out of reach (%d)",