compiler: fix patchlist corruption on switch statement syntax errors

When compiling a switch statement with duplicate `default` cases or a switch
statement with syntax errors before the body block, two error handling cases
were hit in the code that prematurely returned from the function without
resetting the compiler's patchlist pointer away from the on-stack patchlist
that had been set up for the switch statement.

Upon processing a subsequent break or continue control statement, a realloc
was performed on the then invalid patchlist contents, triggering a
segmentation fault or libc assert.

Solve this issue by not returning from the function but breaking the switch
body parsing loop.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler.c b/compiler.c
index f69ee2d..00f9f11 100644
--- a/compiler.c
+++ b/compiler.c
@@ -2448,7 +2448,7 @@ uc_compiler_compile_switch(uc_compiler_t *compiler)
 				uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
 					"more than one switch default case");
 
-				return;
+				break;
 			}
 
 			uc_compiler_parse_consume(compiler, TK_COLON);
@@ -2511,7 +2511,7 @@ uc_compiler_compile_switch(uc_compiler_t *compiler)
 			uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
 				"Expecting 'case' or 'default'");
 
-			return;
+			break;
 		}
 	}